All questions
Question 1
A technology columnist claims that the only reason people worry about data privacy is that they do not understand how encryption works. Therefore, the columnist concludes, public concern about data privacy would disappear if schools required a basic course on encryption. The argument relies on which questionable reasoning pattern?
- It treats a complex issue as having a single cause and ignores other possible reasons for privacy concerns. (correct answer)
- It supports its conclusion by presenting a wide range of empirical studies across multiple countries.
- It assumes that because encryption exists, privacy is impossible to protect.
- It challenges the definition of encryption rather than linking education to privacy attitudes.
- It concludes that because some people understand encryption, no one worries about privacy.
Explanation: This question tests the evaluation of argument logic by identifying oversimplifications in causal explanations. Sound reasoning addresses multifaceted issues with nuanced causes, whereas flawed reasoning attributes complex problems to a single factor. The columnist claims privacy worries stem only from misunderstanding encryption, concluding education would eliminate concerns. This treats privacy as having one cause, ignoring other reasons like data misuse or surveillance. Choice A correctly characterizes this questionable pattern. In contrast, choice E is a distractor that distorts the argument's conclusion about worry. Additionally, choice B fails as the argument does not rely on broad empirical studies.
Question 2
A university administrator argues that because 9 out of the last 10 students caught plagiarizing in introductory courses were first-year students, the university should require all first-year students to complete an additional ethics module. The administrator concludes that first-year students are especially prone to plagiarism and that targeting them will substantially reduce academic dishonesty. The argument is most vulnerable to which criticism?
- It overlooks the possibility that first-year students are overrepresented in introductory courses and therefore more likely to be caught there, even if their propensity to plagiarize is no higher than others'. (correct answer)
- It assumes that any student who plagiarizes must do so intentionally rather than accidentally.
- It provides too many examples of plagiarism cases to support any general conclusion.
- It correctly infers a general tendency from a representative, randomly selected sample of all students.
- It mistakenly concludes that no upper-level students ever plagiarize.
Explanation: This question tests evaluating argument logic, specifically the ability to identify sampling bias in statistical reasoning. Valid statistical inferences require representative samples that accurately reflect the population being studied. The administrator observes that 9 out of 10 students caught plagiarizing in introductory courses were first-year students and concludes that first-year students are more prone to plagiarism. However, this reasoning overlooks a critical confounding variable: first-year students likely make up a much larger proportion of students in introductory courses than in advanced courses. Choice A correctly identifies this flaw—if first-year students constitute 90% of introductory course enrollment, then finding that 90% of plagiarism cases involve first-year students tells us nothing about their relative propensity to plagiarize. Choice E misrepresents the argument by claiming it concludes that no upper-level students plagiarize, when the argument actually focuses on the higher rate among first-year students.
Question 3
A town council argues that because the town’s recycling rate has not improved in three years, the town must choose between two options: either impose steep fines on residents who do not recycle or abandon the recycling program entirely. The council concludes that steep fines are necessary. Which of the following identifies a flaw in the argument's reasoning?
- It presents a false dichotomy by assuming there are only two possible responses, ignoring other measures that might increase recycling. (correct answer)
- It assumes without evidence that recycling has no environmental benefits.
- It draws its conclusion from a carefully controlled experiment with multiple comparison towns.
- It criticizes residents’ moral character rather than addressing recycling policy.
- It claims that because fines have worked in other towns, they will necessarily fail in this town.
Explanation: This question tests the evaluation of argument logic by identifying false dichotomies in decision-making. Sound reasoning considers a full range of options, whereas flawed reasoning presents limited choices as exhaustive, ignoring viable alternatives. The town council claims the town must either impose fines or abandon recycling, concluding fines are necessary. This exemplifies a false dichotomy by overlooking other strategies like education or incentives to boost recycling. Choice A correctly identifies this flaw by noting the assumption of only two options. However, choice E is a distractor that reverses the argument's logic about fines' effectiveness. Likewise, choice D fails because the argument does not criticize residents' character.
Question 4
A financial adviser states that among her clients, those who check their investment accounts daily tend to have lower long-term returns than those who check monthly. She concludes that checking accounts daily causes poor investment performance and advises all investors to avoid frequent monitoring. Which of the following identifies a flaw in the argument's reasoning?
- It assumes that frequent monitoring causes lower returns, even though investors who are already anxious or inexperienced might both monitor more and make worse decisions. (correct answer)
- It presumes that all investors have the same financial goals and time horizons.
- It denies that any investor can ever benefit from tracking account activity.
- It supports its conclusion by showing that daily monitoring always leads to higher fees at all brokerages.
- It concludes that because some clients check daily, all clients must check daily.
Explanation: This question tests the evaluation of argument logic by critiquing reverse causation assumptions. Sound reasoning distinguishes correlation from causation, especially when traits may influence behaviors. The adviser observes lower returns among daily checkers and concludes frequent monitoring causes poor performance. This assumes causation without considering that anxious investors might both check more and perform worse. Choice A correctly identifies this flaw in overlooking self-selection. On the other hand, choice D is a distractor since the argument does not discuss fees or prove through them. Likewise, choice E fails as it misrepresents the argument's generalization.
Question 5
A technology review site argues: "The new AlphaPhone has a battery that lasts 20% longer than last year's model. Longer battery life is what consumers want most in a smartphone. Therefore, the AlphaPhone is the best smartphone on the market." The argument is most vulnerable to which criticism?
- It assumes that because the AlphaPhone is better than its predecessor in one respect, it must be better than all competing phones overall. (correct answer)
- It fails to mention the exact chemical composition of the AlphaPhone battery, which is required to compare smartphones.
- It correctly concludes that battery life is irrelevant to consumers because consumers also care about cameras.
- It proves that the AlphaPhone is the best smartphone because it defines "best" as "has longer battery life."
- It shows that last year's model was the best phone on the market, since the new model improved upon it.
Explanation: This question tests evaluating argument logic, specifically the ability to identify flaws in comparative reasoning. Sound arguments about superiority require comparing all relevant features, not just improvements over previous versions. The review site notes that the AlphaPhone has better battery life than its predecessor and that consumers want longer battery life, then concludes it's the best smartphone on the market. This reasoning assumes that because the phone improved in one dimension compared to its own previous model, it must be superior to all competing phones across all dimensions. Choice A correctly identifies this flaw—being better than a predecessor in one respect doesn't establish superiority over all competitors, especially since other phones might have even longer battery life or excel in other important features. Choice D mischaracterizes the argument as defining "best" solely as battery life, when the argument actually claims battery life is what consumers want most, not that it's the only criterion.
Question 6
A local newspaper reports that in neighborhoods where a new community garden was built, residents report higher satisfaction with their neighborhood than residents in neighborhoods without gardens. The newspaper concludes that building community gardens will increase neighborhood satisfaction and urges the city to fund gardens in every neighborhood. Which of the following identifies a flaw in the argument's reasoning?
- It assumes that the gardens caused the higher satisfaction, even though neighborhoods that received gardens might already differ in resources, engagement, or other improvements. (correct answer)
- It assumes that all residents enjoy gardening as a hobby.
- It claims that neighborhood satisfaction cannot be measured by surveys.
- It concludes that because some neighborhoods have gardens, no neighborhood can have other amenities.
- It relies on the premise that gardens always reduce crime, which is not stated in the argument.
Explanation: This question tests the evaluation of argument logic by detecting selection biases in comparisons. Sound reasoning controls for baseline differences, while flawed reasoning assumes interventions cause outcomes without such controls. The newspaper reports higher satisfaction in neighborhoods with gardens, concluding gardens cause it. This assumes causation while ignoring pre-existing differences in resources or engagement. Choice A accurately identifies this flaw by noting potential confounding factors. In contrast, choice D is a distractor as the argument does not limit amenities exclusively. Likewise, choice E fails because crime reduction is not a premise in the argument.
Question 7
A health columnist claims: "People who take daily vitamin supplements report fewer colds each winter than people who do not. Therefore, vitamins prevent colds, and employers should provide free supplements to reduce sick days." Which of the following best describes the reasoning employed in the argument?
- It infers that a policy will be effective because it resembles a policy that worked in another context.
- It treats a correlation between supplement use and fewer colds as sufficient evidence that supplements cause the reduction in colds. (correct answer)
- It concludes that supplements are ineffective because some supplement users still catch colds.
- It rejects all medical studies in favor of anecdotal evidence from a single individual.
- It establishes by controlled experiment that supplements reduce sick days in the workplace.
Explanation: This question tests your ability to evaluate argument logic by identifying how the argument moves from evidence to conclusion. Sound causal reasoning requires distinguishing between correlation and causation, particularly when dealing with self-reported data. The columnist observes a correlation—people who take vitamin supplements report fewer colds—and immediately concludes that vitamins prevent colds. This reasoning pattern treats the observed correlation as sufficient proof of causation without considering alternative explanations, such as the possibility that health-conscious people both take vitamins and engage in other healthy behaviors that reduce colds. Choice B accurately describes this flawed reasoning pattern by noting that the argument treats correlation as sufficient evidence for causation. Choice D incorrectly characterizes the argument as rejecting medical studies, when the argument actually relies on reported data (which could come from studies) rather than anecdotal evidence from a single person.
Question 8
A university librarian notes that during the past year, the number of students who checked out printed books declined while the number of students who accessed the library’s online database increased. The librarian concludes that students prefer digital sources to printed books and that the university should reduce spending on printed materials and allocate those funds to expanding digital subscriptions. The argument is most vulnerable to which criticism?
- It assumes that the observed shift in usage reflects students’ preferences rather than other factors such as course requirements or changes in database availability. (correct answer)
- It overlooks the possibility that some digital subscriptions may contain inaccurate information.
- It presumes that printed books are always more expensive than digital subscriptions.
- It bases its conclusion on the claim that all students have equal access to reliable internet at home.
- It argues that because printed books are traditional, they must be superior to digital sources.
Explanation: This question tests evaluating argument logic by spotting assumptions in interpreting trends. Sound reasoning involves considering multiple explanations for observed data, whereas flawed reasoning jumps to conclusions based on preferences without evidence. The librarian notes a shift from printed books to digital databases and concludes that students prefer digital sources. This reflects assuming that the usage shift indicates preference, overlooking factors like course requirements or database changes. Choice A correctly characterizes this flaw by pointing out the failure to consider alternative influences on usage. On the other hand, choice E is a distractor that misrepresents the argument, as it does not claim printed books are superior due to tradition. Likewise, choice C fails because the argument does not presume anything about relative expenses.
Question 9
A career counselor claims that graduates who major in philosophy score higher on a certain standardized admissions test than graduates who major in many other fields. The counselor concludes that majoring in philosophy improves test performance and advises students who want high scores to switch their major to philosophy. Which of the following identifies a flaw in the argument's reasoning?
- It assumes that the major itself causes higher scores, without considering that students who choose philosophy may differ in prior skills, interests, or preparation. (correct answer)
- It assumes that standardized tests measure only philosophical knowledge.
- It concludes that because philosophy majors score higher, students in other majors cannot ever score highly.
- It refutes its own conclusion by noting that some philosophy majors do not take the test.
- It accurately establishes causation by randomly assigning students to majors.
Explanation: This question tests the evaluation of argument logic by identifying self-selection in major choices. Sound reasoning isolates causes from correlations, but flawed reasoning assumes majors cause outcomes without considering student differences. The counselor notes higher scores for philosophy majors and concludes the major improves performance. This assumes causation, ignoring that skilled students may choose philosophy. Choice A accurately identifies this flaw by highlighting prior differences. On the other hand, choice E is a distractor since no random assignment is used. Additionally, choice C fails as it overstates the argument's exclusivity.
Question 10
A civic group argues that the city’s public meetings are poorly attended. The group concludes that citizens must not care about local government, and therefore the city should stop holding public meetings and instead let elected officials make decisions without public input. Which of the following identifies a flaw in the argument's reasoning?
- It assumes that low attendance proves citizens do not care, without considering other reasons for low turnout such as meeting times, awareness, or accessibility. (correct answer)
- It assumes that elected officials are always corrupt.
- It argues that because public meetings are important, attendance must be high.
- It bases its conclusion on a comparison between public meetings and jury duty.
- It concludes that if attendance is low now, it will be impossible for attendance ever to increase.
Explanation: This question tests evaluating argument logic by spotting assumptions in interpreting behavior. Sound reasoning considers various reasons for actions, while flawed reasoning infers attitudes directly from outcomes without alternatives. The group observes low meeting attendance and concludes citizens do not care. This assumes low turnout proves apathy, ignoring barriers like timing or awareness. Choice A correctly identifies this flaw by noting overlooked reasons. Conversely, choice C is a distractor that inverts the argument's logic. Likewise, choice E fails because the argument does not claim attendance can never increase.
Question 11
A company’s HR department states that employees who participate in the firm’s mentorship program are promoted at higher rates than employees who do not participate. The department concludes that the mentorship program causes promotions and therefore that requiring all employees to enroll will increase promotion rates across the company. The argument relies on which questionable reasoning pattern?
- It infers causation from a correlation without ruling out the possibility that more ambitious employees are simply more likely to join the program. (correct answer)
- It bases its conclusion on an irrelevant comparison between mentorship and formal training courses.
- It rejects all statistical evidence in favor of personal anecdotes.
- It assumes that promotions are undesirable and therefore should be avoided.
- It proves that mentorship causes promotions by defining a promotion as any outcome of mentorship.
Explanation: This question tests evaluating argument logic by detecting causal assumptions in correlations. Sound reasoning requires evidence that isolates a cause, while flawed reasoning confuses correlation with causation, especially when self-selection may be involved. The HR department observes higher promotions among mentorship participants and concludes the program causes promotions. This pattern assumes causation without addressing that ambitious employees might self-select into the program. Choice A accurately captures this flaw by highlighting the possibility of self-selection bias. In contrast, choice C is a distractor because the argument embraces statistical evidence rather than rejecting it. Similarly, choice E fails as the argument does not engage in circular definition.
Question 12
A professor argues that because students who attend office hours usually earn higher grades than those who do not, the professor’s office hours are the primary reason those students succeed. Therefore, the professor concludes, the department should require all students to attend office hours weekly to raise overall grades. The argument is most vulnerable to which criticism?
- It overlooks the possibility that students who are already more motivated or better prepared are more likely to attend office hours, so attendance may not be the cause of higher grades. (correct answer)
- It assumes that office hours are held at convenient times for every student.
- It claims that grades are not an appropriate measure of student learning.
- It argues that because office hours exist, students must already be attending them.
- It concludes that if office hours help some students, they must help all students equally in every course.
Explanation: This question tests evaluating argument logic by identifying selection biases in correlations. Sound reasoning accounts for pre-existing differences, whereas flawed reasoning attributes outcomes to interventions without such consideration. The professor notes higher grades among office hour attendees and concludes attendance causes success. This overlooks that motivated students may be more likely to attend, so attendance may not cause grades. Choice A accurately critiques this by highlighting potential self-selection. Conversely, choice C is a distractor as the argument does not question grades as a measure. Additionally, choice E fails because the argument does not claim equal benefits for all.
Question 13
A restaurant owner notes that on evenings when live music is scheduled, the restaurant's revenue is typically higher than on evenings without live music. The owner concludes that live music causes higher revenue and decides to schedule music every night. Which of the following criticisms best applies to the argument?
- It assumes that the restaurant's food quality is identical every night, which is unlikely.
- It confuses correlation with causation and does not consider that music nights may coincide with weekends, promotions, or seasonal demand. (correct answer)
- It is invalid because revenue cannot be measured accurately in restaurants.
- It proceeds by analogy between restaurants and concert venues.
- It shows that scheduling music every night will necessarily reduce revenue by increasing costs.
Explanation: This question tests evaluating argument logic by analyzing correlation-causation reasoning. Valid causal inferences require considering alternative explanations for observed patterns. The owner observes higher revenue on music nights and concludes music causes the increase, deciding to schedule it nightly. This reasoning ignores that music nights might coincide with weekends, special promotions, holidays, or periods of naturally higher demand—the music might correlate with but not cause higher revenue. Answer B correctly identifies this as confusing correlation with causation and failing to consider coinciding factors. Answer E incorrectly suggests the argument claims nightly music will reduce revenue, when it actually claims the opposite.
Question 14
A nonprofit states: "Our literacy program is successful because it produces strong reading gains. We know it produces strong reading gains because it is a successful program." On this basis, the nonprofit concludes that the program should be expanded statewide. Which of the following best describes the reasoning employed in the argument?
- It infers that because the program is popular, it must be effective.
- It relies on circular reasoning by using the program's supposed success as evidence for the gains and the gains as evidence for the success. (correct answer)
- It refutes an opposing view by attacking the character of those who doubt the program.
- It is flawed only because it fails to mention the program's annual budget.
- It provides a sound experimental comparison showing that participants outperformed a control group.
Explanation: This question tests evaluating argument logic by identifying circular reasoning. Valid arguments provide independent evidence for their claims rather than using conclusions to support themselves. The nonprofit claims the program is successful because it produces gains, then claims it produces gains because it's successful—each claim relies on the other with no independent evidence. This circular reasoning provides no actual support for expanding the program statewide. Answer B correctly identifies this as circular reasoning where the supposed evidence and conclusion mutually depend on each other. Answer A misses the circularity by focusing only on the popularity-effectiveness inference, which isn't the main flaw here.
Question 15
A manager argues that the company must either allow employees to work fully remotely or accept a significant loss of talented staff. The manager notes that two high-performing employees resigned last month after their requests for full-time remote work were denied. Therefore, the manager concludes, any policy that requires employees to be in the office at least two days per week will inevitably lead to widespread resignations. Which of the following identifies a flaw in the argument's reasoning?
- It assumes that because two employees resigned for one stated reason, many employees will resign for the same reason, without establishing that those two cases are representative. (correct answer)
- It fails to explain why remote work would improve productivity, even though productivity is the only issue under discussion.
- It correctly frames the situation as having only two possible outcomes, since hybrid work policies cannot exist in practice.
- It refutes its own conclusion by admitting that two employees resigned last month rather than this month.
- It demonstrates conclusively that requiring office attendance two days per week will reduce resignations.
Explanation: This question tests evaluating argument logic, specifically the ability to identify hasty generalization from limited evidence. Sound reasoning requires adequate evidence before drawing broad conclusions, especially when making predictions about future behavior. The manager observes that two employees resigned after being denied remote work requests and concludes that any policy requiring office attendance will lead to widespread resignations. This reasoning generalizes from just two cases to predict the behavior of all employees, without establishing that these cases are representative of the broader workforce. Choice A correctly identifies this flaw by pointing out that the argument assumes these two cases represent a general pattern without adequate evidence. Choice C mischaracterizes the argument by claiming it correctly frames only two options, when actually the false dilemma (remote work or resignations) is part of the flawed reasoning, and hybrid policies certainly can exist.
Question 16
A university committee surveyed 25 seniors who attended a new "capstone writing" workshop and found that 22 of them reported feeling more confident about writing. The committee concludes that the workshop is effective and therefore should be required for all students in every major. Which of the following criticisms best applies to the argument?
- It overlooks the possibility that students in some majors have fewer writing assignments than others.
- It draws a broad conclusion about all students from a small, self-reported sample that may not be representative and does not measure actual improvement. (correct answer)
- It assumes without justification that seniors are less capable writers than first-year students.
- It proceeds by analogy, treating the workshop as equivalent to an advanced literature course.
- It establishes with certainty that requiring the workshop will increase the university's graduation rate.
Explanation: This question tests evaluating argument logic by examining how evidence supports a conclusion. Strong arguments use representative samples and measure actual outcomes rather than subjective impressions. The committee surveyed only 25 self-selected seniors about their confidence levels, then concluded the workshop should be mandatory for all students. This reasoning generalizes from a tiny, potentially biased sample (seniors who chose to attend) and measures only self-reported confidence, not actual writing improvement. Answer B correctly identifies both flaws: the unrepresentative sample and the reliance on subjective self-reports rather than objective measures. Answer A misses the point by focusing on writing assignments across majors, which doesn't address the fundamental sampling and measurement problems.
Question 17
A school board member argues: "Our district's students scored below the national average in mathematics. Either we adopt a new math textbook series immediately or we will continue to lag behind indefinitely." The board member adds that a neighboring district adopted a new series and improved its scores the following year. Which of the following best describes the reasoning employed in the argument?
- It presents only two possible options and ignores other plausible strategies that could improve math performance besides changing textbooks. (correct answer)
- It concludes that textbooks are irrelevant because some students dislike reading.
- It demonstrates that the national average is an unreliable statistic because it changes each year.
- It uses a representative sample of districts to show that new textbooks always increase scores.
- It argues that because the district lagged behind, it must have had fewer qualified teachers than other districts.
Explanation: This question tests evaluating argument logic, specifically the ability to identify false dilemmas in reasoning. Sound arguments consider all reasonable alternatives rather than artificially limiting options to create a forced choice. The board member presents only two options—adopt new textbooks immediately or lag behind indefinitely—while ignoring numerous other strategies that could improve math performance, such as teacher training, tutoring programs, curriculum changes, or addressing socioeconomic factors. This reasoning creates a false dilemma by presenting the situation as having only two possible outcomes when many alternatives exist. Choice A correctly identifies this flaw by noting that the argument ignores other plausible strategies besides changing textbooks. Choice D mischaracterizes the argument by claiming it uses a representative sample, when the argument actually relies on a single anecdotal example from a neighboring district.
Question 18
A museum director argues that because the museum's new interactive exhibit increased average visitor time on site from 70 minutes to 95 minutes during the first month after installation, the exhibit must have improved visitor satisfaction. The director concludes that the museum should replace several traditional galleries with additional interactive exhibits to maximize satisfaction. The argument relies on which questionable reasoning pattern?
- It assumes that an increase in time spent at the museum necessarily indicates increased satisfaction, without ruling out other reasons visitors might stay longer. (correct answer)
- It argues that because some visitors dislike interactive exhibits, no interactive exhibit can ever be successful.
- It bases its conclusion solely on a precise definition of "interactive," which is never provided.
- It uses a valid syllogism: all longer visits indicate satisfaction; this visit was longer; therefore satisfaction increased.
- It claims that visitor time increased by exactly 25 minutes at all museums that installed interactive exhibits.
Explanation: This question tests evaluating argument logic by identifying questionable assumptions in causal reasoning. Sound arguments avoid assuming that one possible explanation for an observation must be the correct explanation without considering alternatives. The director observes that visitor time increased after installing an interactive exhibit and assumes this must indicate improved satisfaction. However, this reasoning fails to consider other explanations for why visitors might stay longer—perhaps the interactive exhibit is confusing and takes more time to understand, or perhaps it created bottlenecks that slowed visitor flow through the museum. Choice A correctly identifies this questionable reasoning pattern by noting that the argument assumes longer visits necessarily indicate satisfaction without ruling out other reasons for increased visit duration. Choice D incorrectly describes the argument as using a valid syllogism, when actually the argument's flaw lies in its unwarranted assumption that time equals satisfaction.
Question 19
An environmental group argues: "A recent survey found that residents who live within two miles of a large park are more likely to describe themselves as 'very healthy' than residents who live farther away. Therefore, building a new large park on the city's west side will make west-side residents healthier." Which of the following identifies a flaw in the argument's reasoning?
- It assumes that proximity to a park will cause improved health, without considering that healthier people might be more likely to choose to live near parks or that other neighborhood differences might explain the survey results. (correct answer)
- It assumes that all residents live on the west side, even though some live elsewhere in the city.
- It correctly infers causation because surveys always establish what causes what.
- It claims that no one who lives far from a park is healthy.
- It argues that since parks are enjoyable, the city should eliminate all other recreational facilities.
Explanation: This question tests evaluating argument logic by identifying flaws in reasoning about causation versus correlation. Sound causal reasoning requires considering alternative explanations for observed associations, particularly in observational studies. The environmental group observes that people living near parks report better health and concludes that building a park will make residents healthier. However, this reasoning assumes the proximity causes the health benefits without considering reverse causation (healthier people choosing to live near parks) or confounding variables (neighborhoods with parks might also have better air quality, higher incomes, or other health-promoting features). Choice A correctly identifies these flaws by noting the argument assumes causation without considering self-selection or other neighborhood differences that might explain the correlation. Choice C incorrectly claims the argument correctly infers causation because surveys establish causation, when actually surveys can only show correlation, not causation.
Question 20
A town council states: "We should ban food trucks in the downtown area because downtown restaurants have reported lower revenue since food trucks became more common. Since protecting restaurant revenue is essential to a vibrant downtown, banning food trucks will restore downtown vitality." Which of the following identifies a flaw in the argument's reasoning?
- It assumes that food trucks are the main cause of restaurants' lower revenue, without considering other factors that might explain the decline. (correct answer)
- It mistakenly assumes that restaurants and food trucks serve food, even though only restaurants do.
- It provides an argument that is logically valid because any decline in revenue must have a single cause.
- It attacks the character of food-truck owners rather than addressing the economic issue.
- It concludes that banning food trucks will instantly make every restaurant profitable, regardless of its prices or quality.
Explanation: This question tests evaluating argument logic by identifying flaws in causal reasoning about economic relationships. Sound reasoning requires considering multiple potential causes for observed effects, especially in complex economic situations. The council observes that restaurant revenue declined after food trucks became common and immediately concludes that food trucks caused the decline, then further concludes that banning them will restore vitality. However, this reasoning fails to consider other factors that might explain lower restaurant revenue, such as economic downturns, changing consumer preferences, increased competition from delivery apps, or restaurants' own pricing and quality issues. Choice A correctly identifies this flaw by noting that the argument assumes food trucks are the main cause without considering other explanatory factors. Choice C incorrectly claims the argument is logically valid because declines must have single causes, when in reality complex phenomena like revenue changes typically have multiple contributing factors.