- What is the main purpose of this passage?
Answer: To explain the concept of homeostasis using the example of body temperature regulation.
When you encounter a reading comprehension question asking about the "main purpose" of a passage, you need to identify the author's primary goal—what they're trying to accomplish overall, not just what details they include.
This passage follows a classic structure: it introduces a general concept (homeostasis) and then uses a specific example (human body temperature regulation) to help readers understand that concept. The author defines homeostasis as maintaining stable internal conditions, then immediately illustrates this with how your body keeps its core temperature at 37°C through sweating and shivering. The example serves the broader educational goal of explaining homeostasis.
Answer choice B correctly captures this main purpose—the passage explains homeostasis using body temperature as the illustrative example. Answer choice A is too narrow; while the passage mentions sweating and shivering, these are just supporting details within the larger explanation of homeostasis, not the main focus. Answer choice C misrepresents the passage entirely—the author never argues that temperature regulation is the "most important" biological process; they simply use it as one example. Answer choice D is also incorrect because the passage only discusses human temperature regulation, not comparing different organisms or environments.
For GED Science reading questions, watch out for answer choices that focus on supporting details rather than the main idea. The correct answer usually captures the passage's overarching purpose, while wrong answers often zoom in too narrowly on specific examples or make claims the author never actually made.
- According to the passage, what is a primary characteristic of the stratosphere?
Answer: It contains a high concentration of ozone that absorbs harmful solar radiation.
When you encounter questions about Earth's atmospheric layers, focus on the unique characteristics that distinguish each layer from the others. The passage provides key details about both the troposphere and stratosphere that you need to parse carefully.
The stratosphere's defining feature is its ozone layer, which absorbs harmful ultraviolet radiation from the Sun. This makes choice C correct - the stratosphere does indeed contain a high concentration of ozone that absorbs harmful solar radiation. The passage explicitly states that "the stratosphere contains the ozone layer" and that "it absorbs the majority of the Sun's harmful ultraviolet (UV) radiation."
Choice A is wrong because the passage clearly states that weather occurs in the troposphere, not the stratosphere - "nearly all weather occurs" in the lowest layer. Choice B misrepresents the stratosphere's temperature pattern. The passage specifically mentions that "temperature in the stratosphere actually increases with altitude," which is the opposite of decreasing steadily. Choice D incorrectly identifies the stratosphere's position - it's not the outermost layer but rather lies above the troposphere, and the passage doesn't suggest it's the final atmospheric boundary.
For atmospheric science questions on the GED, pay close attention to the specific characteristics mentioned for each layer. The key distinction here is that the troposphere handles weather while the stratosphere handles UV protection through its ozone concentration. When you see "stratosphere" in a question, immediately think "ozone layer" and "UV absorption."
- According to the passage, which term describes a relationship where one organism benefits and the other is harmed?
Answer: Parasitism
When you encounter questions about biological relationships, focus on who benefits and who is harmed in each interaction. The passage defines three specific types of symbiosis based on these outcomes.
The question asks for a relationship where one organism benefits while the other is harmed. According to the passage, parasitism fits this description exactly: "one species (the parasite) benefits at the expense of the other (the host)." When something happens "at the expense of" another, it means harm or cost is involved. So parasitism describes a one-sided relationship where the parasite gains resources or shelter while damaging its host.
Let's examine why the other choices don't work: (A) Mutualism involves both species benefiting, so neither is harmed. (B) Commensalism means one species benefits while the other is unaffected—not harmed, just neutral. (C) Symbiosis is the broad umbrella term for all close, long-term biological relationships, including mutualism, commensalism, and parasitism, so it's too general to describe this specific harmful relationship.
The correct answer is (D) parasitism.
For GED Science questions about biological relationships, create a simple mental chart: mutualism = both win, commensalism = one wins/one neutral, parasitism = one wins/one loses. Many students confuse commensalism and parasitism, so remember that commensalism involves no harm—the unaffected organism simply doesn't notice the other's presence, like birds nesting in trees.
- According to the passage, what are the primary inputs for photosynthesis in plants?
Answer: Carbon dioxide, water, and sunlight
When you encounter questions about biological processes like photosynthesis, focus on distinguishing between what goes into the process (inputs/reactants) versus what comes out (outputs/products). The passage clearly states that plants "use sunlight to synthesize foods from carbon dioxide and water," which directly identifies the three essential inputs.
The correct answer is C because the passage explicitly mentions that photosynthesis uses three things: sunlight (the energy source), carbon dioxide, and water (the raw materials that get converted into food). These are what plants need to start the photosynthesis process.
Let's examine why the other options are incorrect. Choice A includes organic matter as an input, but organic matter is actually what gets produced during photosynthesis, not what goes into it. Choice B lists oxygen as an input, but the passage states oxygen is "generated as a byproduct," meaning it's an output, not an input. Choice D includes both chlorophyll and oxygen as inputs. While chlorophyll is mentioned in the passage, it's described as a pigment that's involved in the process rather than a raw material that gets consumed. Oxygen, as mentioned, is a product, not an input.
For GED Science questions about biological processes, always carefully read whether the question asks for inputs, outputs, or components involved in the process. These are different categories, and mixing them up is a common trap. Focus on the specific language the passage uses to describe what goes into versus what comes out of the process.
- Based on the mechanism described in the passage, what is the most logical inference about the conditions on Earth if its atmosphere contained no greenhouse gases?
Answer: The Earth's average surface temperature would be much colder, as more of the Sun's energy would escape back into space.
When you encounter questions about Earth's energy balance and the greenhouse effect, focus on understanding how energy flows through our atmosphere and what happens when that flow is altered.
The greenhouse effect works like a thermal blanket: greenhouse gases absorb heat energy that would otherwise escape directly to space and re-radiate some of it back toward Earth's surface. Without these gases, there would be no mechanism to trap this heat energy in our atmosphere.
Choice A correctly identifies what would happen - Earth's surface would be much colder because more of the Sun's energy would escape back into space. Without greenhouse gases to absorb and re-radiate heat, energy would simply bounce off Earth's surface and continue into space unimpeded.
Choice B makes the opposite error, suggesting temperatures would be hotter. This ignores the key role greenhouse gases play in trapping heat - without them, we lose the warming effect entirely. Choice C incorrectly assumes the average temperature would stay the same. While day-night fluctuations might indeed be more extreme without an atmospheric heat buffer, the overall average would drop significantly due to increased heat loss to space. Choice D wrongly suggests the system would remain balanced, failing to recognize that greenhouse gases are essential for retaining thermal energy in our climate system.
Remember: greenhouse gases act as Earth's thermal insulation. Questions about removing or reducing them will typically involve scenarios where Earth loses heat more readily to space, resulting in cooling effects.
- Based on the text, what is the general relationship between temperature and the solubility of solid solutes in water?
Answer: As temperature increases, the solubility generally increases
This question tests your understanding of how temperature affects solubility, a key concept in chemistry that appears regularly on the GED Science exam.
The passage directly states that "for many solids dissolved in liquid water, solubility increases with temperature" and explains that "more solid can be dissolved in hot water than in cold water." This gives you a clear relationship: higher temperature leads to higher solubility for most solid solutes in water.
Answer A correctly captures this relationship. When water temperature rises, the increased molecular motion helps break apart more solute particles and keeps them dissolved, allowing more solid to dissolve.
Answer B reverses the actual relationship. While some gases do become less soluble as temperature increases, the passage specifically discusses solids, which generally become more soluble with heat.
Answer C ignores the temperature-solubility relationship entirely. The passage explicitly contradicts this by stating that temperature does affect how much solid can dissolve.
Answer D introduces an irrelevant factor. While different solutes do have different solubility properties, the passage focuses on the general trend that applies to "many solids" - and that trend is temperature-dependent.
When you encounter solubility questions on the GED, pay close attention to whether you're dealing with solids or gases, as they often behave oppositely with temperature changes. For solids in water, remember the simple rule: hot water dissolves more, cold water dissolves less.
- Based on the text, what is a primary outcome of the process of mitosis?
Answer: The creation of two new cells that are genetically identical to the original cell
When you encounter questions about cell division processes, focus on the key outcomes and purposes of each type. Mitosis is specifically designed for growth, repair, and asexual reproduction, which gives you important clues about what it produces.
The passage clearly states that mitosis creates "two identical daughter cells" where "each daughter cell receives a complete set of chromosomes from the parent cell." This directly points to answer B - mitosis creates two new cells that are genetically identical to the original cell. The text emphasizes that this process "ensures that new cells are genetically identical to the parent cell," making this the primary outcome.
Answer A describes meiosis, not mitosis. Meiosis produces four genetically diverse gametes (sex cells) for sexual reproduction, while mitosis produces identical somatic cells for growth and repair.
Answer C also describes meiosis. The reduction of chromosome number by half is a hallmark of meiosis, which creates haploid gametes from diploid parent cells. Mitosis maintains the same chromosome number as the parent cell.
Answer D describes fertilization, where two gametes fuse to create a genetically unique zygote. This is the opposite of what happens in mitosis, which involves one cell dividing into two.
Remember this key distinction: mitosis produces identical cells for growth and repair, while meiosis produces diverse gametes for reproduction. When you see "identical" and "growth/repair" in a passage about cell division, think mitosis.
- Based on the description of photosynthesis in the passage, which of the following is considered a product of the process?
Answer: Glucose to be used as chemical energy.
When you encounter questions about biological processes like photosynthesis, focus on distinguishing between what goes into the process (reactants) and what comes out of it (products). The chemical equation in the passage is your roadmap: 6CO2+6H2O+Light Energy→C6H12O6+6O2
Looking at this equation, glucose (C6H12O6) appears on the right side of the arrow, making it a product of photosynthesis. The passage confirms this, explaining that photosynthesis "converts light energy into chemical energy stored in glucose" and that plants transform inorganic compounds "into organic fuel." Answer D correctly identifies glucose as a product.
The wrong answers all represent inputs to photosynthesis, not outputs. Answer A (light energy) is clearly listed as a reactant in the equation and described as what plants "use" to power the process. Answer B (carbon dioxide) appears on the left side of the equation as a starting material that gets "taken in" from the atmosphere. Answer C (water) is also a reactant, absorbed by roots and consumed during the process.
Remember that chemical equations work like recipes: ingredients on the left, final products on the right. For the GED Science exam, when analyzing any biological process, always identify what the organism starts with versus what it produces. The arrow in a chemical equation is your friend—it shows the direction of transformation from reactants to products. - Consider the unbalanced equation for the combustion of methane: CH₄ + O₂ → CO₂ + H₂O. According to the principle described in the text, what must be true for the balanced version of this equation?
Answer: The number of carbon, hydrogen, and oxygen atoms must be the same on the left side of the arrow as on the right side.
When you encounter questions about balancing chemical equations, remember that the Law of Conservation of Mass requires that atoms cannot be created or destroyed—only rearranged. This means you must track individual atoms, not molecules or masses of specific compounds.
For the methane combustion equation CH₄ + O₂ → CO₂ + H₂O, balancing requires ensuring equal numbers of each type of atom on both sides. Let's count: the reactant side has 1 carbon, 4 hydrogens, and 2 oxygens. The product side needs the same totals. The balanced equation becomes: CH₄ + 2O₂ → CO₂ + 2H₂O, giving us 1 carbon, 4 hydrogens, and 4 oxygens on each side.
Answer C correctly identifies this principle: the number of carbon, hydrogen, and oxygen atoms must be identical on both sides of the arrow.
Answer A is wrong because the total number of molecules doesn't need to be equal—only the atoms of each element. In our balanced equation, we have 3 reactant molecules but 3 product molecules by coincidence, but this isn't a requirement.
Answer B incorrectly suggests all coefficients must be the same. Different compounds require different coefficients based on their atomic composition.
Answer D makes the error of trying to match masses of individual compounds rather than conserving total mass through atomic balance. The total mass is conserved, but not between specific reactant-product pairs.
Remember: when balancing equations, count atoms of each element separately, not molecules or individual compound masses. Focus on making the atomic inventory identical on both sides.
- Refer to the graph shown to determine at which hour Culture B begins its exponential growth phase.
Answer: Hour 4, when the slope of Culture B sharply increases compared with earlier hours.
On the graph, Culture B shows little growth until about Hour 4, after which the line steepens, indicating exponential (log) growth. Hour 2 still lies in the lag phase, so A is incorrect. Hour 6 is within exponential growth but not its onset, eliminating C. Hour 8 corresponds to the stationary phase, making D wrong.
- What does the term 'carrying capacity' refer to, as defined in the passage?
Answer: The largest population of a particular species that an environment can support indefinitely
Population ecology questions on the GED often test your understanding of key terms that describe how populations interact with their environment. When you encounter terms like "carrying capacity," focus on what limits population growth in real ecosystems.
The passage clearly defines carrying capacity as "the maximum population size of a biological species that can be sustained by that specific environment, given the food, habitat, water, and other resources available." This directly matches answer choice C - the largest population of a particular species that an environment can support indefinitely. The key insight is that carrying capacity represents a sustainable limit based on available resources.
Answer A confuses carrying capacity with biodiversity or species richness. Carrying capacity deals with population size of one species, not the variety of different species in a habitat. Answer B describes exponential growth rate under ideal conditions, which is actually the opposite of carrying capacity - it's what happens when populations aren't limited by environmental constraints. Answer D refers to the minimum viable population, which is the smallest number needed to prevent extinction, not the maximum an environment can sustain.
Notice how the passage also explains what happens when populations exceed carrying capacity: resource scarcity, increased predation, and disease spread cause population decline. This reinforces that carrying capacity is an upper limit.
For GED ecology questions, remember that carrying capacity is always about maximum sustainable population size for one species. Watch for questions that might confuse it with growth rates, minimum populations, or species diversity - these are common distractors.
- Based on the text, what can be concluded about a substance with a pH of 3?
Answer: It is an acidic substance and is one hundred times more acidic than a substance with a pH of 5
This question tests your understanding of the pH scale and its logarithmic nature. When you encounter pH problems, remember that the scale divides substances into three categories based on their relationship to 7, and that the logarithmic property creates dramatic differences between nearby values.
A substance with pH 3 falls well below 7, making it acidic. The key insight is understanding what "logarithmic" means: each whole number difference represents a 10-fold change in acidity. Since pH 3 is two whole numbers below pH 5, you calculate: 10 × 10 = 100 times more acidic. This confirms that answer C is correct.
Let's examine why the other options fail. Answer A incorrectly categorizes pH 3 as neutral, but only pH 7 is neutral—anything below 7 is acidic. Answer B makes the opposite error, calling pH 3 basic, when basic substances must have pH values above 7. Answer D describes pH 3 as "weakly acidic" and "very close to neutral," but pH 3 is actually quite acidic since it's four full units away from neutral pH 7.
The trap in this question lies in underestimating how the logarithmic scale works. Students often think pH 3 and pH 5 are only "a little different" because 3 and 5 seem close numerically.
Study tip: For GED Science pH questions, always identify whether the pH is above or below 7 first, then remember that each unit difference equals a 10-fold change in strength. Practice calculating these logarithmic differences—they appear frequently on the exam.
- Based on the text, what is the principal role of the central nervous system (CNS)?
Answer: To serve as the body's main information processing and command center
When you encounter questions about body systems, focus on distinguishing between the different roles and functions of each component. The nervous system has two main divisions with distinct but complementary functions.
The passage clearly states that the CNS "acts as the primary control center, processing information and making decisions." This directly supports answer B - the CNS serves as the body's main information processing and command center. The brain and spinal cord work together to receive information, analyze it, and determine appropriate responses.
Let's examine why the other options miss the mark. Answer A describes the function of the peripheral nervous system (PNS), not the CNS. The passage explicitly states that the PNS "is made up of the nerves that connect the CNS to the rest of the body." Answer C only captures half of the CNS's role - while it does receive sensory information, this option ignores the crucial processing and decision-making functions. Answer D describes the execution phase that actually occurs through the PNS, which "carry out commands from the CNS to the muscles and glands."
Think of the CNS as the "headquarters" - it's where decisions are made and plans are formed. The PNS functions more like the "communication network" that delivers messages to and from headquarters.
For GED Science questions about body systems, always pay attention to the distinction between control/processing functions versus communication/transport functions. The passage will typically give you clear clues about which system does what - use those details to guide your answer.
- A population of deer is introduced to an island with abundant resources and no natural predators. Based on the text, which statement best predicts the long-term population trend for these deer?
Answer: The deer population will grow rapidly at first, but will then likely decrease sharply as it depletes the island's finite resources and exceeds the environment's limits.
This question tests your understanding of carrying capacity and population dynamics, particularly what happens when a population is introduced to a new environment without natural controls.
When deer are introduced to an island with abundant resources and no predators, they start far below the carrying capacity, so they'll experience rapid exponential growth initially. However, the key insight from the passage is that populations often overshoot their carrying capacity, especially when lacking natural predators to control their numbers. Once they exceed what the environment can sustainably support, they'll deplete resources faster than those resources can replenish, leading to a sharp population crash.
Answer B correctly captures this boom-bust cycle: rapid initial growth followed by a sharp decline as resources become depleted and the population exceeds environmental limits.
Answer A is wrong because populations don't simply stabilize permanently at high levels—they must still respect the carrying capacity, and adaptation doesn't create unlimited resources. Answer C incorrectly assumes the deer population will somehow self-regulate to match resource replenishment, but without predators or other limiting factors, deer typically can't control their own reproduction effectively. Answer D is wrong because abundant resources and lack of predators would actually promote rapid population growth, not keep the population small and stable.
For GED Science questions about population ecology, remember that introduced species without natural controls often follow a predictable pattern: exponential growth, overshoot, then crash. Real populations rarely grow smoothly to a perfect equilibrium.
- According to the passage, what is inertia?
Answer: The tendency of an object to continue in its current state of motion
When you encounter questions about Newton's laws and motion concepts, focus on understanding the definitions provided in the passage rather than relying on outside knowledge.
The passage explicitly defines inertia as "an object's resistance to any change in its state of motion." This means inertia describes an object's tendency to keep doing what it's already doing - staying at rest if it's at rest, or continuing to move at the same speed and direction if it's already moving. Answer choice D captures this concept perfectly by describing inertia as "the tendency of an object to continue in its current state of motion."
Let's examine why the other choices are incorrect. Choice A describes a force that causes acceleration, but inertia isn't a force - it's a property that resists changes in motion. Choice B defines mass, which the passage mentions is related to inertia (more mass means more inertia), but mass and inertia are different concepts. Choice C describes velocity (speed with direction), which is about an object's motion itself, not its resistance to changing that motion.
The passage also reinforces this understanding by connecting inertia directly to Newton's First Law, which describes how objects resist changes to their motion unless acted upon by unbalanced forces.
For GED Science success, always check if the passage provides explicit definitions before applying outside knowledge. When you see questions about physics concepts like inertia, look for key phrases that distinguish between the concept itself and related but different ideas like force, mass, or velocity.
- Orchids often grow on the high branches of tropical trees. The orchids gain access to sunlight and are not rooted in the soil, while the trees are unaffected by the orchids' presence. Based on the definitions in the text, how is this relationship best classified?
Answer: Commensalism, because the orchid benefits by gaining a better position for sunlight access, while the tree remains completely unaffected by this interaction.
When analyzing symbiotic relationships, you need to carefully assess what happens to each organism involved. The key is determining whether each species is helped, harmed, or unaffected by the interaction.
In this orchid-tree scenario, the orchid clearly benefits by gaining access to sunlight in the forest canopy without competing for soil nutrients. The critical detail is that the tree remains "unaffected" by the orchid's presence. The orchid doesn't take nutrients from the tree or harm it in any way—it simply uses the tree as a platform. This one-sided benefit with no effect on the host organism perfectly defines commensalism, making C correct.
Option A incorrectly calls this parasitism. While the orchid does use the tree for support, parasitism requires the host to be harmed. Since the tree is unaffected, this isn't parasitism. Option B suggests mutualism, claiming the tree benefits from aesthetic appeal or pollinator attraction. However, the passage explicitly states the tree is unaffected, and you shouldn't add benefits not mentioned in the scenario. Option D completely misapplies terminology—predator-prey relationships involve one organism consuming another, not simply occupying space.
Remember this pattern for symbiosis questions: always identify the effect on both organisms first. If one benefits and the other is unaffected, it's commensalism. If both benefit, it's mutualism. If one benefits while harming the other, it's parasitism. Don't overthink potential benefits that aren't explicitly stated in the scenario.
- According to the process described in the text, which combination of geological features would one most likely expect to find along the coast of a continent where an oceanic plate is colliding with it?
Answer: A deep ocean trench offshore and a chain of volcanoes on the continent, resulting from the sinking plate.
When you encounter questions about tectonic plate interactions, focus on matching the type of plate boundary with its characteristic geological features. The passage describes a specific scenario: oceanic-continental convergence with subduction.
The correct answer is B because subduction zones create two signature features. First, as the dense oceanic plate bends downward and sinks beneath the continental plate, it forms a deep ocean trench just offshore. Second, as the descending oceanic plate melts in the hot mantle, the resulting magma is less dense than surrounding rock and rises upward, breaking through the continental crust to form a chain of volcanoes. This perfectly matches what the passage describes.
Answer A describes a mid-ocean ridge, which forms where plates move apart (divergent boundaries), not where they collide. Transform faults involve plates sliding past each other horizontally, neither of which applies to this convergent scenario.
Answer C describes continental rifting, where a continent begins splitting apart. This creates rift valleys and extensive lava flows, but occurs within continents, not at oceanic-continental boundaries.
Answer D describes continental-continental collision, where two landmasses of similar density crash together. This creates large mountain ranges through compression and folding, but without the volcanic activity that characterizes oceanic-continental subduction.
Remember this pattern: oceanic-continental convergence always produces the "trench and volcano" combination. The heavier oceanic plate always goes down (creating the trench), while the melting creates magma that rises through the continental plate (forming volcanoes). This is one of the most predictable relationships in plate tectonics.
- What principle must be followed for a chemical equation to be correctly balanced, according to the text?
Answer: The total mass of the reactants must equal the total mass of the products
This question tests your understanding of the law of conservation of mass, a fundamental principle in chemistry that governs how chemical equations must be balanced.
The passage clearly states that "the law of conservation of mass is upheld" in balanced chemical equations, meaning "mass is neither created nor destroyed in a chemical reaction." This directly leads to the requirement that "the total mass of the reactants must equal the total mass of the products." Answer choice D restates this principle exactly.
Let's examine why the other options are incorrect. Choice A suggests products must have greater mass than reactants, which violates conservation of mass—mass cannot be created during a reaction. Choice B claims states of matter must remain constant, but this is false; many reactions involve phase changes (like combustion producing water vapor from liquid fuel). Choice C states reactions must produce new substances, and while this is often true, it's not the principle that determines whether an equation is properly balanced—you can have a correctly balanced equation regardless of whether truly "new" substances form.
The key distinction is that this question asks specifically about the principle for balancing equations, not general characteristics of chemical reactions. Only the conservation of mass principle (equal total mass of reactants and products) directly determines how to balance chemical equations.
Remember: When you see questions about balanced chemical equations on the GED, always think "conservation of mass." The masses on both sides must be equal—atoms are rearranged, never created or destroyed.
- According to the passage, why do the action and reaction forces described by Newton's Third Law not cancel each other out?
Answer: Because the forces are applied to two separate, interacting objects.
Newton's Third Law questions often test whether you understand the relationship between action-reaction force pairs and how they interact with objects in a system.
The key insight here is that action and reaction forces act on different objects, which prevents them from canceling out. When you push on a wall, you exert a force on the wall, and simultaneously the wall exerts an equal and opposite force on you. Since these forces act on separate objects (you and the wall), they cannot cancel each other out. Forces can only cancel when they act on the same object. This is why option B correctly identifies that the forces are applied to two separate, interacting objects.
Looking at the incorrect answers: Option A suggests the reaction force is weaker, but Newton's Third Law explicitly states the forces are equal in magnitude. Option C claims the forces occur at different times, but action and reaction forces are always simultaneous - they happen at exactly the same moment. Option D incorrectly states that the forces act perpendicular to each other, when Newton's Third Law specifically requires them to be opposite in direction (180 degrees apart, not 90 degrees).
When studying Newton's Third Law, remember this crucial distinction: action-reaction pairs never act on the same object. If you see forces canceling out in a physics problem, those are different forces acting on the same object, not an action-reaction pair. This concept frequently appears on science exams, so always identify which objects the forces are acting upon.
- According to the passage, what is a primary characteristic of the inner planets?
Answer: They are relatively small, dense, and made mostly of rock and metal
When you encounter questions about planetary characteristics, focus on the key distinguishing features that separate different groups of planets in our solar system.
The passage clearly states that inner planets are "smaller, denser, and composed mainly of rock and metal." This directly supports answer choice B, which accurately captures all three primary characteristics of terrestrial planets. The text explicitly categorizes Mercury, Venus, Earth, and Mars as the inner planets with these specific properties.
Looking at the incorrect options: Choice A describes the outer planets, not the inner ones. The passage states that gas and ice giants are "much larger, less dense, and composed primarily of gases like hydrogen and helium" - the exact opposite of inner planet characteristics. Choice C reverses the size relationship; the passage clearly indicates that outer planets are "much larger" than inner planets, making inner planets relatively smaller. Choice D confuses terminology and planetary groups. "Ice giants" specifically refers to Uranus and Neptune in the outer solar system, not the inner planets, and the passage doesn't mention surface temperatures as a defining characteristic.
For GED Science questions about astronomy, pay close attention to how scientific texts categorize and contrast different groups of objects. The exam often tests whether you can accurately match stated characteristics to the correct group. Always refer back to the specific language in the passage rather than relying on outside knowledge, and watch for answer choices that mix up characteristics between different planetary groups.
