- Which choice best states two central ideas of the passage?
Answer: Reaching orbit takes engineering solutions like staging, and missions also rely on orbit planning and reusable parts.
Central ideas are the main points an author builds across a passage, not small details. This passage develops two of them: that reaching orbit requires engineering solutions such as staging, and that successful missions also depend on careful orbit planning and on new ways to lower cost. Choice B states both of these main points. Choice A is wrong because it lists two minor details instead of the central ideas. Choice C is wrong because the passage never says space travel is easy or that fuel no longer matters, and Choice D is wrong because it treats one small detail as if it were the whole passage.
- Which statement best identifies the topic and a central idea of the passage?
Answer: Topic: microbes in the human body. Central idea: helpful microbes support digestion and can affect health by interacting with diet and the immune system.
The topic is what the whole passage is about, and a central idea is a main point it makes about that topic. The passage discusses microbes in the human body, and its main point is that helpful microbes support digestion and can affect health through both diet and the immune system. The choice naming microbes in the human body captures the full topic and both central ideas the passage develops. The vitamins choice narrows the topic to just one detail the passage mentions in passing, so it misses the broader focus. The antibiotics choice treats one supporting example as if it were the passage's single main point, ignoring digestion and the immune system. The immune-system choice also shrinks the passage to one part and wrongly claims digestion is only there to introduce it, when digestion is developed as a central idea in its own right. Only one choice names the whole topic and the passage's actual main points.
- Which option best states two central ideas of the passage?
Answer: The passage lays out the reasons certain neighborhoods stay warmer and shows how thoughtful design choices can protect people and save energy.
A central idea is a passage's biggest overall point, not one small fact. The correct choice captures both large points the passage builds: the reasons some neighborhoods stay warmer and the design changes that protect people and lower energy use. The choice about taller buildings and wind names only tiny details from the first paragraph, so it misses the passage's true main ideas. The choice claiming sunlight strikes cities more strongly misreads the text, which says dark surfaces absorb and slowly release heat, not that the sun itself shines harder on cities. The choice blaming air conditioning as the single biggest cause of warmth also misreads the passage, which lists air conditioning only as something that adds to demand during heat waves, never as the reason cities stay warm. Only one choice states two ideas that are both large and both actually supported by the whole passage.
- Which statement is best classified as a supporting detail rather than a central idea?
Answer: Sleep can help the brain organize information during learning.
A central idea is a big point the whole passage builds, while a supporting detail is one smaller fact that backs it up. That the brain changes with experience, that change takes practice and time, and that it aids recovery are the passage's main ideas. The point about sleep helping the brain organize information is one specific detail under the "change takes effort" idea. Choice A is that detail, so it is correct, while B, C, and D each state a central idea.
- Read the passage and answer the question.
When people hear the word "compost," they often picture a pile of leaves rotting in a corner of a yard. In reality, composting is a controlled process that turns food scraps and yard waste into a dark material that gardeners can mix into soil. One central reason compost matters is that it keeps organic waste out of landfills. In a landfill, food waste is buried without much oxygen, and it can produce methane, a gas that traps heat in the atmosphere.
Compost also helps soil work better. The finished material can improve the soil's ability to hold water, which is useful during dry weeks. It can also make soil less compact, allowing roots to spread and earthworms to move through the ground. Some communities collect compost in bins the way they collect recycling, then send it to facilities that monitor temperature and moisture so the process breaks down waste efficiently.
Not every item belongs in a compost bin, though. Meat and dairy can attract pests, and certain "compostable" plastics only break down in industrial facilities, not in a backyard pile. Because of these limits, many compost programs teach residents what to include and what to leave out.
Which choice best provides an objective summary of the passage?
Answer: The passage explains what composting is, describes how it can reduce landfill waste and improve soil, and notes that successful composting requires following guidelines about which materials to include.
An objective summary reports the passage's central ideas factually, without adding opinion and without treating one detail as the whole point. The correct choice does this: it states what composting is, that it can cut landfill waste and improve soil, and that it works best when people follow guidelines about materials—the three main ideas the passage develops.
The choice claiming everyone "should" compost because landfills are "terrible" and composting is the "only responsible choice" adds opinion and judgment the passage never makes, so it is not objective.
The choice about collection bins and monitored facilities is accurate but only a supporting detail from one paragraph; a summary must cover the whole passage, not zoom in on a single fact.
The choice saying the passage centers on avoiding meat, dairy, and certain plastics also mistakes a detail for the main point—those limits appear only at the end, and the passage never claims they are why composting programs exist.
- How is the central idea that warming oceans harm coral reefs developed across the passage?
Answer: By explaining the bleaching process, describing what happens when heat stress repeats, and tying those effects to the need to limit ocean warming.
To see how a central idea is developed, trace the steps the passage takes. It first explains bleaching, then describes what repeated heat stress does to a reef, and finally links those effects to the need to limit ocean warming. The choice that follows that build is correct. The option about reefs mattering to people picks a supporting section and names pollution as the main fix, but the passage says long-term health depends on limiting warming, not mainly on pollution. The option claiming damaged reefs always recover and that human action barely matters contradicts the passage, which says repeated heat stress can kill reefs and that limiting warming matters. The option about nurseries covers only one response effort and wrongly dismisses ocean temperature, which the passage names as the trigger for bleaching. Only one choice traces the full path from cause to effect to solution.
- Which statement best describes how the central idea about trust is developed in the passage?
Answer: It is developed by explaining why some people may hold back information and by giving examples of steps health departments take to increase cooperation.
An author develops a central idea through the reasons and examples given for it. Here, the trust idea grows from an explanation of why people might hold back information, such as fearing blame or job loss, followed by examples of steps that build cooperation, like protecting privacy and offering food or housing. The best answer names both of those moves. Another choice claims trust matters most during surges and that workers skip cooperation then, but the passage says surges only shift focus to high-risk settings, not that trust is abandoned. A different choice says trust grows automatically and lists diseases spreading quickly, but the passage never says trust is automatic and does not build the trust idea from disease spread. The last wrong choice mentions job-loss fears but then points to exact medical tests, which the passage never describes, so it does not develop the trust idea.
- Which choice best states a central idea of the passage?
Answer: The Internet depends on physical hardware, and that hardware shapes how fast and reliable service is.
A central idea is the main point an author develops with supporting details, not a single fact. This passage explains that the Internet runs on physical hardware such as routers, cables, and servers, and that this hardware shapes how fast and reliable service is. Choice B states both parts of that main point, so it best captures a central idea. Choice A is wrong because it claims the Internet has no physical parts, which the passage directly contradicts. Choice C names a true detail about ocean cables but treats it as the whole idea, and Choice D takes one small detail about data centers and treats it as the passage's main point.
- Which choice best separates a central idea from a supporting detail in the passage?
Answer: Central idea: recycling is part of reducing waste and saving resources. Supporting detail: making aluminum from recycled cans uses far less energy than making it from raw ore.
A central idea is a big, overall point the passage makes, while a supporting detail is a smaller fact that backs it up. The passage's main point is that recycling helps reduce waste and save resources, and the fact that recycled aluminum takes far less energy is one example that supports it — so that pairing is correct. Another choice flips the two, treating aluminum being recyclable (a detail) as the central idea while calling a real central idea the detail. One choice names a true central idea but then labels another central idea as if it were just a supporting detail, so the two parts do not fit together as a big point and a small fact. The last choice overstates the passage: it says sorting is 'the only thing that matters,' but the passage says communities also need the right factories and buyers, so sorting is important but not the only requirement.
- Which choice best explains how the passage develops its central ideas?
Answer: It introduces supply chains with an example, explains the strengths and weaknesses of long chains, and then describes how businesses lower disruption risk.
The passage moves through a clear structure. It first defines supply chains using the T-shirt example, then explains that long chains are efficient but fragile, and finally describes how some businesses lower their risk. The correct choice traces exactly those three steps in order.
The choice that says faraway factories are 'always a mistake' misreads the passage, which explains that companies pick them for good reasons like lower costs and special skills. The choice that predicts empty shelves 'will soon disappear' overstates the passage, which only says risk choices can lower the chance of empty shelves, not end them. The choice that claims lowering costs is 'the only goal' contradicts the passage, which shows businesses accepting higher costs to reduce risk. Only the first choice matches what the passage actually does from beginning to end.
- Which choice best states two central ideas of the passage?
Answer: Cafeteria food waste has several causes, and reducing it takes practical changes in routine, along with systems like sharing and composting.
A central idea is a main point the passage develops. This text builds two: that cafeteria waste has several causes, and that cutting it takes real changes in routine plus systems like share tables and composting. The choice naming several causes and practical routine changes with sharing and composting captures both, so it is correct. The option that calls short lunch periods the single cause is wrong because the passage lists several causes and treats composting as one method among prevention and sharing. The option about stopping fresh food and relying on reminders contradicts the text, which says change in routine matters more than reminders. The option treating composting as the main focus overstates one part the passage mentions last, and it misreads share tables as being mainly about health rules rather than reducing waste. Only one choice names both central ideas without twisting or shrinking them.
- Which choice best states two central ideas of the passage?
Answer: African American families migrated for economic and for safety and civil-rights reasons, and the movement changed both Southern and Northern communities over time.
A central idea is a main point the author develops across the passage, not one small detail. This passage builds two: families migrated for economic reasons and for safety and civil rights, and the movement reshaped both the communities they left and the ones they joined. The correct choice names both of these ideas together. The choice about better weather is wrong because the passage never mentions weather and says Northern jobs, not vanished Southern ones, drew families. The choice about letters and newspapers takes a single detail and overstates it, claiming those sources 'guaranteed' an easy, racism-free life—but the passage says racism still existed in the North. The choice about crowded housing turns one effect into an absurd 'single most serious problem the country ever faced' and ignores the passage's other effects, like new businesses, churches, music, and political change. Only one choice captures the passage's two big ideas without distorting the text.
- Which choice correctly identifies the topic and a central idea from the passage?
Answer: Topic: renewable energy; Central idea: renewable sources can reduce greenhouse gas emissions compared to fossil fuels.
The topic is the broad subject the whole passage covers, and a central idea is a main point the passage makes about it. The passage as a whole is about renewable energy, and one of its clearly stated main points is that renewable sources produce fewer greenhouse gases than fossil fuels—so the choice naming renewable energy and lower emissions is correct. Naming solar panels as the topic is too narrow, since solar is only one example, and the passage never claims solar is the cheapest option. Naming climate change as the topic mistakes a detail for the whole subject; the passage treats climate change as one benefit to weigh, not the single goal behind every decision. Naming electricity costs shrinks the broad topic, and its claim ignores the passage's point that over many years renewable costs can come close to fossil-fuel costs, especially when fuel prices rise. Only one choice matches both the passage's true topic and one of its actual central ideas.
- How are the two central ideas developed and connected in the passage?
Answer: The passage first explains how search rankings actually work, then shows how that knowledge leads to steps for judging a page's credibility.
The passage builds two central ideas in order. First it explains how search engines rank pages using signals like links and word matches. Then it uses that understanding to introduce steps for judging whether a page is trustworthy, showing that knowing how rankings work is why the checking steps matter. The correct answer captures both this order and this connection. One choice reverses that connection, claiming the checking steps stand apart and don't really depend on understanding rankings — but the passage links them directly. Another choice gets the ranking idea right but then twists it, saying popular high-ranked pages are the most accurate, when the passage warns that popular pages can still contain mistakes. The last choice narrows the passage down to only researching an author, treating that single step as the whole skill and ignoring both the ranking idea and the other checking steps the passage lists. Only the correct answer keeps both central ideas and shows how the first develops into the second.
- Which choice best provides an objective summary of the passage?
Answer: The passage describes block scheduling, noting that longer periods allow deeper activities but also create challenges like missed instruction and focus problems, and that schools adjust the model to manage trade-offs.
An objective summary fairly states all the main points without adding an opinion. The passage presents two central ideas—that longer periods can support deeper learning and that they also create challenges—and it ends by noting that schools adjust the model. The choice that captures the benefits, the challenges, and those adjustments is the best summary. The choice about the benefits of longer periods is only partly right: it covers the advantages but drops the challenges, and it adds the opinion that most schools should adopt the schedule, which the passage never says. The choice about activities mistakes the examples (labs, debates, workshops) for the main point, when they are only support for one central idea. The choice about missing school seizes on a single detail and turns it into the passage's argument, ignoring everything else. Only the full, balanced summary fits what an objective summary must do.
- Which choice best summarizes the passage objectively?
Answer: Factory work raised production but created harsh conditions, and workers and lawmakers responded with unions and new laws.
An objective summary states a text's main points fairly, without adding opinions or overstating what is said. This passage makes two connected points: factory work increased production but created harsh conditions, and workers and lawmakers responded with unions and new laws. The best answer captures both points in neutral language. The choice about "courageous" unions and "greedy" owners is wrong because it uses loaded, one-sided wording that adds opinion the text never states. The choice claiming the passage explains how machines worked and that city life "beat" farm life names a focus the passage does not have and adds a judgment it never makes. The choice saying laws "quickly ended child labor and solved every safety problem" overstates the results, which the passage denies when it says "The problems did not disappear."
- Which option best summarizes the passage objectively?
Answer: The passage describes how drought is measured with several indicators and explains how it affects farming, cities, and energy while prompting different responses.
An objective summary covers the whole passage's main points without twisting them or adding opinions. The correct choice fairly captures all three ideas: how drought is measured, how it affects farming, cities, and energy, and how communities respond. The choice about snowpack takes one small detail and overstates it, then adds the false claim that careful farming alone could prevent most droughts—the passage never blames farmers or promises prevention. The choice about repairing pipes and reusing wastewater covers only the response section and wrongly ranks those actions above measurement, a judgment the passage never makes. The choice about predicting droughts starts accurately but ends with a claim the passage never supports: it says measurements help leaders plan, not that anyone can predict exactly when and where the next drought will hit. Only the first choice summarizes the full passage without distortion.
- Which choice is a central idea of the passage, not just a supporting detail?
Answer: Cities built water-treatment plants and improved waste removal to reduce disease and improve health.
A central idea sums up what the whole passage is about, not one fact from it. The passage returns again and again to how cities improved their water and waste systems in order to fight disease and protect people's health, which is exactly the point that cities built water-treatment plants and improved waste removal to reduce disease and improve health. The choice about cleaner water lowering typhoid deaths is true, but it names one result of those changes rather than the passage's overall message. The choice about leaders arguing over taxes and budgets is only a detail explaining why progress was uneven, not the main idea. The choice about trash and sewers spreading disease describes the early problem the reforms were meant to fix, so it is background, not the central point. Only the first choice covers the passage as a whole.
- How does the passage develop the idea that renewable energy can save money over time?
Answer: By comparing the upfront costs with long-term factors like free fuel and steady maintenance, showing how the total cost can become competitive.
To trace how an idea is developed, follow the reasoning the passage lays out. For the money idea, it first admits the high upfront cost, then explains the long-term savings, free fuel and steady repair costs, and concludes that the total cost can match fossil fuels over time. Choice B describes that development, so it is correct. Choice A describes a how-it-works structure the passage does not use, Choice C invents an argument about fossil fuels running out, and Choice D narrows the passage to batteries while dropping cost.
- Which choice best states two central ideas of the passage?
Answer: Cover crops improve soil by reducing erosion and adding organic matter, and they bring economic and management trade-offs that can create both costs and savings.
A central idea is a main point the author develops across the passage, not one detail stretched too far. This passage builds two ideas together: cover crops protect and rebuild soil, and they bring trade-offs in cost and management. The answer naming both erosion-and-organic-matter and the cost-and-savings trade-offs captures both, so it is best. The choice calling cover crops the cheapest option gets one idea right but adds a claim the passage denies—it says they are 'not a simple, free solution.' The choice about always planting legumes twists a small detail into a rule the author never states and ignores the trade-offs entirely. The choice ending with erosion as 'the single biggest problem facing farms everywhere' overstates one detail and drops the soil-rebuilding and economic ideas, so it names only part of the passage. Only the correct choice states both central ideas without exaggeration.
