QUESTION EXPLANATIONS

1. (B) — After some brief scene-setting in the first paragraph, lines 6-52 are given over to describing the character of Titee both at the moment the story begins and in general; hints that he is doing something unusual begin with lines 73-76, continue with his parents’ conversation in lines 77-84, and culminate in the final sentence “something unparalleled in the entire history of his school-life” (lines 93-94). (B) encompasses both of these aspects of the passage, so it is correct. The passage does not focus on the teacher, only describes one student (Titee), and describes Titee in detail rather than briefly, so (A) is incorrect. There is nothing about Titee’s family’s history in the passage, so (C) is incorrect. The passage does describe a child who attends school, but his daily routine is not given, so (D) is incorrect.

2. (C) — The description of the setting includes words such as “cold,” “sharp,” “gloomy,” and “dismal,” and also says that the “blasts” of wind “made men shiver”; these choices combine to emphasize the harshness of the surroundings and suggest that unpleasant things are coming soon. (C) accurately captures this effect. Words like “gloomy” and “dismal” have connotations which are too negative to create a cheerful mood, so (A) is incorrect. The mood conveyed in the paragraph is negative, but it does not suggest something actively frightening or malicious as opposed to just unpleasant, so (B) is incorrect. Although the mood suggests bad things will happen soon, no tragedy is present in the relevant paragraph, and the hardship of the cold wind is not depicted as something unique to the neighborhood, so (D) is incorrect.

3. (A) — It is conventional to say that wind blows “gusts”; replacing the word “blasts” with “gusts” in the original sentence results in a sentence that makes sense and does not mean something significantly different, so (A) is correct. It is not conventional to describe the movement of wind in “explosions” (which imply the destruction of matter from within, which is not implied in the passage), “wails” (which refers primarily to sound, while the context of the original word refers to force), or “shockwaves” (which has both a specific physical meaning not suggested by the original sentence, and a metaphorical meaning that does not apply to the clearly physical action of the original sentence). Thus, (B), (C), and (D) are incorrect.

4. (D) — The paragraphs in question describe Titee’s teacher’s negative attitude towards him, as demonstrated by the highly critical adjectives with which she thinks of him (such as “idle,” “lazy,” and “troublesome”); the explanation for this attitude is pinned to behaviors such as his enjoyment of practical jokes and his lack of interest in language lessons compared to games. (D) captures both the teacher’s feelings and the given causes for those feelings. The paragraph suggests that Titee does not work very hard in school, so (A) is incorrect. The paragraph mentions Titee’s teacher’s frustration with him specifically, but does not go further to suggest she is dissatisfied with her career overall, so (B) is incorrect because it is not supported by the passage. The lines in question do not mention science at all, so (C) is incorrect.

5. (D) — After showing the ways that Titee stuggles in school, the paragraph referenced in this question describes a number of areas about which Titee is both curious and knowledgeable, such as the anatomy of insects and the geography of his neighborhood; these are attributes commonly associated with intelligence, so (D) is correct. The paragraph in question does not make any reference to Titee getting in trouble, so (A) is incorrect. The paragraph does not contain any further information about his teacher, so (B) is incorrect. The paragraph does not refer to his parents at all, so (C) is incorrect.

6. (A) — Titee complains out loud about the weather in lines 11-12 and 46-48; the passage also highlights the unpleasant physical effects of the cold on him in lines 6-9 and 43-45. From these examples, we can infer that the weather is unpleasant for him and contributes to his bad mood; thus, (A) is correct. Although we can infer that Titee is sometimes the cause of his teacher’s bad mood, the passage contains no direct information about Titee’s attitude toward his teacher to suggest that the reverse is true. It may be the case that he does not like his teacher, given how often he gets in trouble, but there is not sufficient evidence in the passage to support that, especially considering that Titee runs to school with “a joyous whoop”, so (B) is incorrect. The passage does not indicate how Titee feels about his parents, so (C) is incorrect. The passage refers to the streets that are familiar to Titee as “wondrous,” suggesting that he has some fondness for his neighborhood; furthermore, nothing in the passage directly connects Titee’s negative feelings to his neighborhood, so (D) is incorrect.

7. (B) — The lines in (B) convey Titee’s strong negative opinion of the weather; (B) thus matches both the topic and the correct answer of the previous question, so it is correct. (A) does not connect current events to his mood; in fact, it does not convey any information about his mood, nor does it refer to the weather, so it is incorrect. (C) contains hints that his mood might be more than it seems, but it does not suggest what the causes of his mood may be, and it does not mention the weather; thus, it is incorrect. (D) does refer to the weather, but it discusses his teacher’s perception of him, not his own mood, so it is incorrect.

8. (D) — Titee’s mother wonders “what he’s up to” (line 77) directly after the passage states that he “scarcely ate his breakfast,” opting instead to leave in a rush; this is especially significant given the reference to his large appetite in lines 25-28. Thus, (D) is correct. While the passage does say that he rushed his breakfast, it does not directly indicate that he spoke little, nor does it suggest that he normally speaks a great deal during breakfast, so (A) is incorrect. The passage does not show his parents’ reaction to Titee’s lateness for school, only his teacher’s; thus, (B) is incorrect. The passage does not say that Titee forgets his books at home, so (C) is incorrect.

9. (C) — The lines in (C) convey the unusualness of Titee’s behavior at the breakfast table, which is what prompts his parents, immediately after this selection, to wonder what is going on; (C) aligns with both the topic and the correct answer of the previous question, so it is correct. (A) and (B) both come before the unusual behavior at breakfast that makes his parents wonder about him, so they cannot support the assertion made in the previous question and are therefore incorrect. (D) takes place a full day after his parents voice their speculation about him, so it cannot support the assertion made in the previous question and is therefore incorrect.

10. (B) — In the original sentence, “mechanism” is being compared to “plan,” so the correct answer must be one that can be a synonym for both words. Replacing “mechanism” with “operation” in the original sentence results in a sentence that makes sense and means roughly the same thing, so (B) is correct. “Machinery” is used to refer to physical machines, but the original context does not suggest that Titee favors physical objects in his classroom misbehavior, so (A) is incorrect. “Device” is also more often used to refer to physical objects, and also carries connotations of greater specificity than “mechanism,” so (C) is incorrect. “Channel” suggests a preexisting network through which plans would flow, but Titee operates alone and, in the teacher’s view, is always coming up with new plans, so (D) is incorrect.

11. (C) — Lines 10-15 describe the evolution of a bird’s beak, which formed from small plates of bone that fused together, making (C) correct. The premaxillae are the bones that fused together to form the beak, not what a beak developed into, so (A) is incorrect. The bones did not separate to form a beak, as suggested in (B), and the beak developed from bones rather than lightweight tissue, making (D) incorrect.

12. (D) — In this sentence, “struck” is used to describe the scientists’ awed surprise at the production of a certain protein in chicken embryos. This is best captured by (D), the only answer choice with a clearly positive connotation. Scientists were not thumped (A), ignited (B), or afflicted (C) by this fact; these words do not make sense in context and all have negative or neutral connotations, and are thus incorrect. (A) and (B) are also more literal synonyms of the word “struck,” but it is used in a figurative way in the original sentence.

13. (D) — The scientists' attempt at reverse evolution is described in lines 40-47 of Passage 1. They implanted a microscopic bead into chicken embryos in order to inhibit the development of the proteins that usually lead to beak formation; this disrupted beak development, as stated in answer (D). The bead decreased rather than increased production of these proteins, so (A) is incorrect. The section mentions nothing about surgical removal of developing beaks (B) or the splicing of genes (C), making both of these choices incorrect.

14. (A) — Dr. Ralph S. Marcucio’s reaction to the scientists’ work is discussed in lines 48-53, including his theory that the altered anatomy seen in the experiments might just be a result of dying tissue, rather than reverse evolution as the scientists suggest. Thus, his attitude might best be described as skeptical or cautious, captured in (A). He is not encouraging (B) or sincere (D) (while Marcucio may be sincere in his beliefs, this is not the same as having a sincere attitude). His critique also does not imply that he is envious of the scientists’ work (C).

15. (D) — The lines referenced in (A), (B), and (C) are all from parts of the passage before Dr. Marcucio is mentioned. The lines in (D) reference Dr. Marcucio’s theory that the altered chicken anatomy might be due to dying tissue rather than reverse evolution, which forms the basis of his uncertainty about the results of the experiment. This demonstrates why Dr. Marcucio feels cautious about Dr. Bhullar and Dr. Abzhanov’s research.

16. (D) — Here, “clear” is used to describe that the traces found by paleontologists on a dinosaur fossil in China were indisputably from feathers; this meaning is indicated by the description of the fossil as “persuasive evidence” (lines 56-57) Answer (D) is most similar to this meaning. The traces described are not transparent (A), vibrant (B), or unblemished (C); these are all synonyms of clear that typically used for physical descriptions, while here “clear” is referring to how obviously the traces came from feathers. Thus, these answers are all incorrect.

17. (A) — Lines 59-62 describe how the discovery of featherlike traces on dinosaur remains is not new, but the completeness of such a fossil is. The author thus most likely mentions this in order to describe the novelty, or significance, of the finding (A). These lines do not represent a counterpoint (B) and describe the significance of the study rather than downplaying it (C). They are not the main point of the passage, so (D) is incorrect as well.

18. (C) — Passage 2 discusses, in the final paragraph, that “these particular dinosaurs” (referencing the dromaeosaurs mentioned in the second paragraph) are not necessarily descendants of the birds but may be descendants of the ancestors of birds, implying that birds and dromaeosaurs share a common ancestor. Thus, (C) is correct. The passage does not state that birds and dromaeosaurs share no relationship (D) or that birds are direct descendants of these dinosaurs (A), nor does it mention at any point whether birds and dromaeosaurs coexisted (B).

19. (D) — Lines 90-92 (D) directly reference the portion of the passage that establishes the relationship between dromaeosaurs and birds. The lines in choice (A) discuss the discovery of fossils, not this relationship, while (C) references lines discussing characteristics of nonavian dinosaurs, making this choice irrelevant as well. The lines in (B) reference a portion of the passage that discusses the physical makeup of these dinosaurs, but does not shed light on their relationship to birds.

20. (A) — Passage 2 describes the discovery of a new fossil dinosaur and then delves into the evolutionary relationship between dinosaurs and birds, while Passage 1 describes a study by two scientists on reverse engineering bird beaks. Only Passage 1 describes an experiment, so (A) is correct. Both passages touch on the relationship between dinosaurs and birds (B) and discoveries that may link them (C), as well as the process of bird evolution (D).

21. (A) — Passage 2 focuses on the discovery of a fossil, and Passage 1 focuses on the discovery of the process of beak development in birds. Only Passage 1 discusses genetic changes, making (A) correct. Neither passage discusses widespread acceptance (or lack thereof) of their findings (B), or the taint of controversy (D). Both passages discuss the bone structure of birds (C), particularly in lines 10-15 in Passage 1 and in lines 83-86 in Passage 2.

22. (C) — Kennedy discusses his compassion for and desire to help the “other Americans” he mentions in the passage, so he is not resigned (B) or bemused (D). His passionate feelings are best described by choice (C); words like “disgrace” (line 25) show Kennedy feels the situation is negative, and his desire to change it fuels the rest of his speech. Answer choice (A) does not match the gravity of Kennedy’s attitude and approach in this passage.

23. (B) — In lines 9-11 (B), Kennedy discusses how he does not feel the conditions faced by other Americans are acceptable, and calls for change, supporting the idea that he is outraged by the situation. The lines referenced in (A) only provide information about the other Americans, not about Kennedy’s reaction to them. The lines referenced in (C) and (D) do not refer to the other Americans directly.

24. (B) — Kennedy discusses the size of the Gross National Product, but also mentions all of the different areas that contribute to it, including air pollution, cigarette advertising, the destruction of nature, weapons, etc. He continues that it does not count our children’s health, their education, our beautiful poetry, etc. We can thus infer that he believes it measures (sometimes unsavory) economic outputs, but not personal or moral worth (B). He does not call for its increase (C), nor does he suggest that it is necessary to help Americans avoid poverty and disgrace (A). Though Kennedy discusses what the Gross National Product does not measure, he focuses on more intangible things like joy and integrity, not other industries; thus, (D) is also incorrect.

25. (D) — Lines 57-59 reference a portion of the passage where Kennedy describes how the Gross National Product measures everything “except that which makes life worthwhile,” supporting the previous answer that the GNP leaves personal and moral values out of its measurements. The lines referenced in (A) and (B) come before any discussion of the GNP and do not provide any support for the answer to the previous question; they are thus incorrect. The lines in (C) only discuss the size of the GNP, not whether it measures personal or moral value, and is thus incorrect.

26. (A) — Kennedy mentions in lines 18-21 how, with the unselfish spirit exhibited by Americans, “we can do better” to help the other Americans. Answer (A) best captures this. Kennedy does not attribute the unselfish spirit to government (C) or industry (D), nor does he limit it specifically to the men of the Appalachia (B).

27. (A) — Here, “erase” is used in reference to the possibility of ending material poverty, so “eliminate”(A) is correct. It would not be standard English phrasing to say material poverty was “deleted” (B) or “cancelled” (D), and “obliterate” (C) has too strong of a connotation to match the tone of the original sentence. Thus, these answer choices are all incorrect.

28. (B) — Kennedy mentions “the poverty of satisfaction, purpose, and dignity” as he asserts that Americans are afflicted by this lack of meaning and personal value, instead focusing too much on material gain. Thus, he is referring to more than just economic issues faced by Americans; this is best summarized by answer choice (B). The remaining answer choices are all incorrect as they suggest Kennedy is speaking only of the economy in a monetary sense. He is not expressing worry about economic failure (A) or suggesting Americans should focus more on economic goals (C), nor is he suggesting that fixing the economy will help solve this moral crisis (D).

29. (A) — Here, Kennedy repeats “it counts” multiple times when describing negative aspects of the U.S. economy that are counted in the Gross National Product. His aim is to emphasize the variety and large number of such unsavory aspects that contribute to the GNP (A). He is not aiming simply to show how large the GNP is (B), nor is he making an argument about how the GNP is calculated (C). We also see from the elements that Kennedy chooses to highlight (the jails, the environmental destruction, the military weapons) that his aim is not to demonstrate the GNP’s diversity (D), but rather to shine a light on a certain unpleasant subset of it.

30. (D) — Here, “allow for” is used to describe elements that the Gross National Product does not count or include, so choice (D) is correct. Kennedy is not implying that the GNP is conceding (A), pondering (B), or granting (C) these elements.

31. (C) — Kennedy mentions that the Gross National Product does not measure a variety of personal and moral aspects in America, including the integrity of public officials (line 53), so (C) is correct. In the previous paragraph, Kennedy mentions that the GNP does measure air pollution (lines 37-38), weapons (line 44), and advertising for cigarettes and violent toys (lines 38 and 47), so (A), (B), and (D) are incorrect.

32. (C) — The passage focuses mainly on where the ancestors of Native Americans went for 15,000 years, after splitting from their Asian relatives. The author posits that they lived on the Bering Land Bridge during this time, and spends the majority of the passage fleshing out this idea, making (C) correct. The author does not suggest that these ancestors are unrelated to populations in the East (A), or that they are more closely related to modern Native Americans (B). The passage focuses on how these ancestors lived on the land bridge, not about how they crossed it, so (D) is also incorrect.

33. (C) — Lines 26-33 lay out the argument that the author and his cowriters set forth in their Science article about the Bering Land Bridge, which the author goes on to discuss in the rest of the passage, so (C) is correct. Answer (A) focuses too specifically on the genetic link between the people of ancient East Asia and modern Native Americans, a topic not extensively discussed in the passage. Similarly, answer (B) is too specific, focusing on the possibility of northeast Siberia’s habitation during a warm period. Answer (D) just provides information about the size of the Bering Land Bridge, which is a minor detail irrelevant to the main point of the passage.

34. (C) — In lines 1-4, the author discusses the long history of the theory about humans crossing the land bridge to the Americas. However, the author focuses in the passage on the idea that humans actually inhabited this land bridge, and didn’t just cross it, so (C) is the most appropriate answer choice. The author is not ridiculing the theory, nor does the rest of the passage fully “debunk” it so much as modify it, so (D) is incorrect. Since the author later expands and modifies this theory, rather than accepting it in its original form, we can also infer that his primary purpose was not to explain and support it (A) or to establish its authority (B).

35. (D) — The author states in lines 54-55 that the land bridge began to disappear beneath the sea after the last ice age, making (D) correct. Since the author is postulating that humans lived on the Bering Land Bridge thousands of years ago, we can eliminate (A). Answer (B) is incorrect, as Beringia is the land bridge itself, not the destination reached by crossing the bridge. The author describes the land bridge as shrub tundra (line 41) rather than a “rich, forested area,” so (C) is incorrect.

36. (C) — In this line, “supported” is used to describe how the shrub tundra allowed mammals like elk and sheep to survive, making (C) the best answer. It did not brace (A), hold (B), or reinforce (D) these animals, which have more literal and direct meanings and are thus incorrect.

37. (C) — The passage describes how the shrub tundra “had the one resource people needed most to keep warm: wood” (lines 45-46), making (C) correct. Line 53 references the “bitter cold of Arctic winter nights;” thus, the climate was not temperate and mild, eliminating (A). Though the passage does mention large mammals, it does not suggest that this resource was the main reason that the shrub tundra was hospitable to humans, so (B) is incorrect. Similarly, though the passage does mention the burning of bones for fuel, (D) is incorrect because it was not the presence of these bones that made the shrub tundra hospitable.

38. (B) — Answer (B) is correct as it references lines that discuss the presence of wood, directly supporting the previous answer. Answer (A) references large mammals and answer (C) references bones and fuel, both of which were incorrect answer choices from the previous question. Answer (D) is irrelevant, referencing changing conditions in the Beringian region rather than providing support that the shrub tundra’s wood resources were essential to early humans’ survival in that region.

39. (B) — Here, “retreating” is being used to describe the melting glaciers. The glaciers are not retiring (A), recoiling (C), or falling (D)—these choices are unlikely to be used in scientific writing. Rather, the glaciers can be described as disappearing, as seen in answer choice (B).

40. (B) — The table shows the spread of genetic lineages from both west to east and east to west, so we can infer that (B) is correct. The passage discusses the genetic links between the people of Asia and the Americas, so (A) is incorrect. Answer (C) is not supported by either the table or the passage, which discuss the flow of people and not their isolation. Further, any periods of isolation on Beringia would have lasted thousands, not hundreds, of years. Answer (D) does not make sense in the context of the passage or table, since neither one touches on genetic transfer between modern humans, and is thus incorrect.

41. (A) — The table shows that the swift peopling of the Americas began about 15,000 years ago, so (A) is most likely to be true and therefore correct. The initial peopling of Beringia occurred 25,000 years ago, not 2,500 years ago, so (C) is incorrect. The table shows migration in both directions, making (D) incorrect. However, while there is some evidence of back migration shown in the table, it is not specific enough to support the idea that humans were moving from the Americas to Asia over a certain period of time, and thus (B) is also incorrect.

42. (B) — The passage focuses on ravens’ social dynamics and dominance calls within their own and other social groups, best captured by answer (B). It is not focused on the difficulty of studying ravens (A) or on the limitations of the study discussed (D), which are only mentioned in lines 80-86. Though the passage does touch on dominance and dominance reversal calls, it does so to demonstrate ravens’ sophisticated social abilities and not their battle for dominance, so (C) is too narrow.

43. (C) — Answer (A) references lines that focus specifically on one part of Massen’s research methodology, and so is too narrow to support the previous answer. Similarly, answer (B) is too narrow, discussing the study’s investigation into raven’s recognition of behavior in other social groups, without stating any conclusions about this possibility. Answer (C) directly references lines that discuss the major findings of the study, which are the focus of the passage, about ravens’ recognition of social calls within their own and others’ communities. Thus, it is the correct answer. Answer (D) is incorrect, as it focuses specifically on lines skeptical of the study’s findings.

44. (A) — The passage describes that a dominance reversal call occurs when a “lower-ranking bird does not respond in a submissive way to a dominance call,” which can often lead to confrontations and changes in social structure (lines 24-29). Thus, (A) is correct. Dominance reversal calls do not come from higher-ranking ravens, making all the variations described in (B), (C), and (D) incorrect.

45. (C) — Answer (C) references the lines that directly describe the purpose of dominance reversal calls, and so is correct. (A) does not describe any type of call at all, while (B) describes a call made by submissive ravens that recognizes higher-ranking ravens, rather than challenging them as a dominance reversal call does. Answer (D) does not reference calls either, and is thus incorrect.

46. (D) — Here, “normal” is used to describe the usual sorts of conflicts ravens engage in. These conflicts are not familiar (A), mainstream (B), or average (C), but rather typical, and so (D) is correct.

47. (A) — In these lines, the author describes that community changes pose a higher risk to female ravens, which are lower ranked than males and have more limited access to food. This helps to explain the result seen in the study (and mentioned in the previous sentence) that female ravens were more stressed than males when they heard dominance reversal recordings, making (A) correct. This information does not suggest a further potential area for research (B), summarize the conclusion of the study (C), or seem controversial (D). Thus, these are not likely to be why the author included this information, and (B), (C), and (D) are incorrect.

48. (B) — Here, “impressive” is used to describe the important findings of the study. This is best captured by (B), as the findings are not poignant (A), rousing (C), or inspirational (D). These synonyms all carry a more sensational connotation than would typically be used to described a scientific finding.

49. (B) — The passage describes how ravens experienced less stress when hearing dominance reversal calls in other communities, versus in their own (lines 66-70). Thus, they experienced more stress when they heard these calls within their own communities, making (B) correct. Answer (A) directly contradicts this, making it incorrect. The passage does not discuss the effects of dominance reversal calls in juvenile vs. adult ravens, making (C) incorrect. The passage also does not discuss the stress experienced in response to low-ranking females, so (D) is incorrect. The discussion of stress in response to female reversal calls generally (lines 56-59) only suggests that it would not produce much stress for male ravens.

50. (D) — Alex Thornton is cautious in his discussion of the research, discussing how the results may have been affected by the fact that captive ravens were used. Though he doesn’t go so far as to say the results are erroneous (A), he is not convinced of the study’s applicability, so (D) is correct. He doesn’t mention the study’s funding (B) or suggest that he plans to redo the experiment (C).

51. (A) — The final paragraph describes how “raven intelligence may have evolved along with the development of social communities” (lines 89-91), so answer (A) is correct. The passage does not suggest that this social development evolved along with ravens’ politics, dominant personalities, or captivity, eliminating (B), (C), and (D) respectively.

52. (C) — The graph shows how ravens’ stress response was greater in response to unexpected vs. expected in-group stimuli, most closely matching answer choice (C). The graph does not break down female vs. male responses, so (B) can be eliminated. The graph measures stress responses, not expressions of surprise, so (A) is incorrect. The graph is comparing stress responses, but does not indicate what percentage of ravens, if any, exhibit no stress response, eliminating (D).