100 RCs for Digital SAT - 3 | 100 Reading Comprehensions for Digital SAT PDF Download

Directions:

• The questions in this section address a number of important reading and writing skills.
• Each question includes one or more passages, which may include a table or graph.
• Read each passage and question carefully, and then choose the best answer to the question based on the passage(s).
• All questions in this section are multiple-choice with four answer choices. Each question has a single best answer. 

Q21: Passage
Text 1: Ecologists have long wondered how thousands of microscopic phytoplankton species can live together near ocean surfaces competing for the same resources. According to conventional wisdom, one species should emerge after outcompeting the rest. So why do so many species remain? Ecologists’ many efforts to explain this phenomenon still haven’t uncovered a satisfactory explanation.
Text 2: Ecologist Michael Behrenfeld and colleagues have connected phytoplankton’s diversity to their microscopic size. Because these organisms are so tiny, they are spaced relatively far apart from each other in ocean water and, moreover, experience that water as a relatively dense substance. This in turn makes it hard for them to move around and interact with one another. Therefore, says Behrenfeld’s team, direct competition among phytoplankton probably happens much less than previously thought.

Q. Based on the texts, how would Behrenfeld and colleagues (Text 2) most likely respond to the “conventional wisdom” discussed in Text 1?
(a) By arguing that it is based on a misconception about phytoplankton species competing with one another
(b) By asserting that it fails to recognize that routine replenishment of ocean nutrients prevents competition between phytoplankton species
(c) By suggesting that their own findings help clarify how phytoplankton species are able to compete with larger organisms
(d) By recommending that more ecologists focus their research on how competition among phytoplankton species is increased with water density
Ans: (A)

• Choice A is the best answer because based on Text 2, it represents how Behrenfeld and colleagues would most likely respond to the “conventional wisdom” discussed in Text 1. The conventional wisdom cited holds the opinion that when there is species diversity within a phytoplankton population, “one species should emerge after outcompeting the rest”—that is, after being so successful in competing for resources that the other species vanish from the population. However, Text 2 explains that according to Behrenfeld and colleagues, phytoplankton are so small and spaced so far apart in the water that there is “much less” direct competition for resources within phytoplankton populations than scientists had previously thought.
• Choice B is incorrect because Text 2 never discusses whether routine replenishment of ocean nutrients affects competition between phytoplankton species.
• Choice C is incorrect because the interspecies competition discussed in both texts is specifically between phytoplankton species, and neither text considers whether phytoplankton compete for resources with larger nonphytoplankton species.
• Choice D is incorrect because according to Text 2, Behrenfeld and colleagues argue that water density decreases, not increases, competition between phytoplankton species.

Q22: Passage
In 2014, Amelia Quon and her team at NASA set out to build a helicopter capable of flying on Mars. Because Mars’s atmosphere is only one percent as dense as Earth’s, the air of Mars would not provide enough resistance to the rotating blades of a standard helicopter for the aircraft to stay aloft. For five years, Quon’s team tested designs in a lab that mimicked Mars’s atmospheric conditions. The craft the team ultimately designed can fly on Mars because its blades are longer and rotate faster than those of a helicopter of the same size built for Earth.

Q. According to the text, why would a helicopter built for Earth be unable to fly on Mars?
(a) Because Mars and Earth have different atmospheric conditions
(b) Because the blades of helicopters built for Earth are too large to work on Mars
(c) Because the gravity of Mars is much weaker than the gravity of Earth
(d) Because helicopters built for Earth are too small to handle the conditions on Mars
Ans: (A)

• Choice A is the best answer because it presents an explanation about a helicopter that is directly supported by the text. The text states that Mars’s atmosphere is much less dense than Earth’s, and as a result, the air on Mars doesn’t provide the resistance required to support the blades of a helicopter built for Earth and to keep the helicopter aloft. In other words, a helicopter built for Earth can’t fly on Mars because of the differences in the two planets’ atmospheres.
• Choice B is incorrect because instead of stating that the blades of helicopters built for Earth are too large to work on Mars, the text indicates that the helicopter built to fly on Mars actually has even longer blades than a helicopter built for Earth.
• Choice C is incorrect because the text never addresses the role of gravity on Mars or on Earth; instead, it focuses on atmospheric conditions.
• Choice D is incorrect because the text doesn’t indicate that helicopters built for Earth are too small to operate in the conditions on Mars. In fact, the text states that the size of the helicopter built to fly on Mars is the same size as a helicopter built for Earth, even though it has longer blades that rotate faster.

Q23: Passage
In West Africa, jalis have traditionally been keepers of information about family histories and records of important events. They have often served as teachers and advisers, too. New technologies may have changed some aspects of the role today, but jalis continue to be valued for knowing and protecting their peoples’ stories.

Q. Which choice best states the main idea of the text?
(a) Even though there have been some changes in their role, jalis continue to preserve their communities’ histories.
(b) Although jalis have many roles, many of them like teaching best.
(c) Jalis have been entertaining the people within their communities for centuries.
(d) Technology can now do some of the things jalis used to be responsible for.
Ans: (A)

• Choice A is the best answer because it best states the main idea of the text. According to the text, jalis’ traditional role has been to maintain information about families’ histories and significant events. The text goes on to say that although technological changes have altered jalis’ role somewhat, jalis are still valued for preserving the histories of their communities.
• Choice B is incorrect because the text says nothing about jalis’ views of the various tasks they perform. There is no information to support the idea that many jalis prefer teaching to other tasks.
• Choice C is incorrect because the text doesn’t describe jalis as being sources of entertainment. Rather, jalis are presented as valued sources of knowledge. Additionally, the text gives no indication of how long jalis have been serving their communities.
• Choice D is incorrect because the main focus of the text is on jalis’ role and their continued value despite the effects of technology, not on what technology can now do. Although the text indicates that jalis’ role has changed as a result of technological changes, the text doesn’t present any specific information about technology performing tasks that jalis once performed.

Q24: Passage
In 1934 physicist Eugene Wigner posited the existence of a crystal consisting entirely of electrons in a honeycomb-like structure. The so-called Wigner crystal remained largely conjecture, however, until Feng Wang and colleagues announced in 2021 that they had captured an image of one. The researchers trapped electrons between two semiconductors and then cooled the apparatus, causing the electrons to settle into a crystalline structure. By inserting an ultrathin sheet of graphene above the crystal, the researchers obtained an impression—the first visual confirmation of the Wigner crystal.

Q. Which choice best states the main idea of the text?
(a) Researchers have obtained the most definitive evidence to date of the existence of the Wigner crystal.
(b) Researchers have identified an innovative new method for working with unusual crystalline structures.
(c) Graphene is the most important of the components required to capture an image of a Wigner crystal.
(d) It’s difficult to acquire an image of a Wigner crystal because of the crystal’s honeycomb structure.
Ans: (A)

• Choice A is the best answer because it most accurately states the main idea of the text. According to the text, Eugene Wigner hypothesized that a crystal could exist that would be composed of electrons and have a honeycomb-like shape. The text goes on to say that the existence of the Wigner crystal remained unconfirmed until Feng Wang and colleagues were able to make an impression of one using two semiconductors and an ultrathin sheet of graphene. Thus, the main idea is that researchers have obtained the most definitive evidence to date of the existence of the Wigner crystal.
• Choice B is incorrect because the text focuses on one kind of crystal—the Wigner crystal—and doesn’t discuss crystalline structures in general.
• Choice C is incorrect because the text describes in general the process Wang and colleagues followed to obtain an impression of the Wigner crystal; it doesn’t address the relative importance of each component in that process.
• Choice D is incorrect because the text doesn’t state that researchers had a hard time getting an impression of the Wigner crystal because of its honeycomb structure. Nothing in the text indicates why it took so long to prove the existence of this crystal or take an impression of it.

Q25: Passage
When digging for clams, their primary food, sea otters damage the roots of eelgrass plants growing on the seafloor. Near Vancouver Island in Canada, the otter population is large and well established, yet the eelgrass meadows are healthier than those found elsewhere off Canada’s coast. To explain this, conservation scientist Erin Foster and colleagues compared the Vancouver Island meadows to meadows where otters are absent or were reintroduced only recently. Finding that the Vancouver Island meadows have a more diverse gene pool than the others do, Foster hypothesized that damage to eelgrass roots increases the plant’s rate of sexual reproduction; this, in turn, boosts genetic diversity, which benefits the meadow’s health overall.

Q. Which finding, if true, would most directly undermine Foster’s hypothesis?
(a) At some sites in the study, eelgrass meadows are found near otter populations that are small and have only recently been reintroduced.
(b) At several sites not included in the study, there are large, well-established sea otter populations but no eelgrass meadows.
(c) At several sites not included in the study, eelgrass meadows’ health correlates negatively with the length of residence and size of otter populations.
(d) At some sites in the study, the health of plants unrelated to eelgrass correlates negatively with the length of residence and size of otter populations.
Ans: (c)

• Choice C is the best answer because it presents a finding that, if true, would weaken Foster’s hypothesis that damage to eelgrass roots improves the health of eelgrass meadows by boosting genetic diversity. The text indicates that sea otters damage eelgrass roots but that eelgrass meadows near Vancouver Island, where there’s a large otter population, are comparatively healthy. When Foster and her colleagues compared the Vancouver Island eelgrass meadows to those that don’t have established otter populations, the researchers found that the Vancouver Island meadows are more genetically diverse than the other meadows are. This finding led Foster to hypothesize that damage to the eelgrass roots encourages eelgrass reproduction, thereby improving genetic diversity and the health of the meadows.
• If, however, other meadows not included in the study are less healthy the larger the local otter population is and the longer the otters have been in residence, that would suggest that damage to the eelgrass roots, which would be expected to increase with the size and residential duration of the otter population, isn’t leading meadows to be healthier. Such a finding would therefore weaken Foster’s hypothesis.
• Choice A is incorrect because finding that small, recently introduced otter populations are near other eelgrass meadows in the study wouldn’t weaken Foster’s hypothesis.
• Choice B is incorrect because the existence of areas with otters but without eelgrass meadows wouldn’t reveal anything about whether the damage that otters cause to eelgrass roots ultimately benefits eelgrass meadows.
• Choice D is incorrect because the health of plants other than eelgrass would have no bearing on Foster’s hypothesis that damage to eelgrass roots leads to greater genetic diversity and meadow health.

Q26: Passage
While researching a topic, a student has taken the following notes:

• NASA uses rovers, large remote vehicles with wheels, to explore the surface of Mars.
• NASA’s rovers can’t explore regions inaccessible to wheeled vehicles.
• Rovers are also heavy, making them difficult to land on the planet’s surface.
• Microprobes, robotic probes that weigh as little as 50 milligrams, could be deployed virtually anywhere on the surface of Mars.
• Microprobes have been proposed as an alternative to rovers.

Q. The student wants to explain an advantage of microprobes. Which choice most effectively uses relevant information from the notes to accomplish this goal?
(a) Despite being heavy, NASA’s rovers can land successfully on the surface of Mars.
(b) Microprobes, which weigh as little as 50 milligrams, could explore areas of Mars that are inaccessible to NASA’s heavy, wheeled rovers.
(c) NASA currently uses its rovers on Mars, but microprobes have been proposed as an alternative.
(d) Though they are different sizes, both microprobes and rovers can be used to explore the surface of Mars.
Ans: (b)

• Choice B is the best answer. The sentence explains an advantage of microprobes, noting that because microprobes weigh as little as 50 milligrams, they can explore areas inaccessible to rovers.
• Choice A is incorrect. The sentence indicates that rovers can land successfully on Mars despite their weight; it doesn’t explain an advantage of microprobes.
• Choice C is incorrect. While the sentence mentions that microprobes have been proposed as an alternative to rovers, it doesn’t explain an advantage of microprobes.
• Choice D is incorrect. The sentence emphasizes a similarity between microprobes and rovers; it doesn’t explain an advantage of microprobes.

Q27: Passage
While researching a topic, a student has taken the following notes:

• Abdulrazak Gurnah was awarded the 2021 Nobel Prize in Literature.
• Gurnah was born in Zanzibar in East Africa and currently lives in the United Kingdom.
• Many readers have singled out Gurnah’s 1994 book Paradise for praise.
• Paradise is a historical novel about events that occurred in colonial East Africa.

Q. The student wants to introduce Paradise to an audience unfamiliar with the novel and its author. Which choice most effectively uses relevant information from the notes to accomplish this goal?
(a) Abdulrazak Gurnah, who wrote Paradise and later was awarded the Nobel Prize in Literature, was born in Zanzibar in East Africa and currently lives in the United Kingdom.
(b) Many readers have singled out Abdulrazak Gurnah’s 1994 book Paradise, a historical novel about colonial East Africa, for praise.
(c) A much-praised historical novel about colonial East Africa, Paradise (1994) was written by Abdulrazak Gurnah, winner of the 2021 Nobel Prize in Literature.
(d) Paradise is a historical novel about events that occurred in colonial East Africa, Abdulrazak Gurnah’s homeland.
Ans: (c)

• Choice C is the best answer. The sentence effectively introduces Paradise to an audience unfamiliar with the novel and its author, describing Paradise as a historical novel about colonial East Africa and its author as the winner of the 2021 Nobel Prize in Literature.
• Choice A is incorrect. While the sentence introduces Abdulrazak Gurnah to an audience unfamiliar with the author, it doesn’t effectively introduce Paradise.
• Choice B is incorrect. While the sentence provides background information about Paradise, it doesn’t effectively introduce the novel to an audience unfamiliar with its author.
• Choice D is incorrect. While the sentence provides background information about Paradise, it doesn’t effectively introduce the novel to an audience unfamiliar with its author.

Q28: Passage
While researching a topic, a student has taken the following notes:

• Ulaanbaatar is the capital of Mongolia.
• The city’s population is 907,802.
• Ulaanbaatar contains 31.98 percent of Mongolia’s population.
• Hanoi is the capital of Vietnam.
• The city’s population is 7,781,631.
• Hanoi contains 8.14 percent of Vietnam’s population.

Q. Which choice most effectively uses information from the given sentences to emphasize the relative sizes of the two capitals’ populations?
(a) Mongolia’s capital is Ulaanbaatar, which has 907,802 people, and Vietnam’s capital is Hanoi, which has 7,781,631 people.
(b) The populations of the capitals of Mongolia and Vietnam are 907,802 (Ulaanbaatar) and 7,781,631 (Hanoi), respectively.
(c) Even though Hanoi (population 7,781,631) is larger than Ulaanbaatar (population 907,802), Ulaanbaatar accounts for more of its country’s population.
(d) Comparing Vietnam and Mongolia, 7,781,631 is 8.14 percent of Vietnam’s population, and 907,802 is 31.98 percent of Mongolia’s.

Ans: (c)

• Choice C is the best answer. The sentence emphasizes the relative sizes of the capital cities’ populations, noting that even though Hanoi has more people overall, Ulaanbaatar accounts for a larger percentage of the people in its country.
• Choice A is incorrect. While the sentence indicates the population size of each capital, it fails to emphasize their sizes relative to each other or to their countries’ overall population sizes.
• Choice B is incorrect. While the sentence indicates the population size of each capital, it fails to emphasize their sizes relative to each other or to their countries’ overall population sizes.
• Choice D is incorrect. The sentence emphasizes the population sizes of the two countries; it fails to mention the capitals.

Q29: Passage
While researching a topic, a student has taken the following notes:

• One of history’s greatest libraries was the House of Wisdom in Baghdad, Iraq.
• It was founded in the eighth century with the goal of preserving all the world’s knowledge.
• Scholars at the House of Wisdom collected ancient and contemporary texts from Greece, India, and elsewhere and translated them into Arabic.
• Writings included those of the Greek philosopher Aristotle and the Indian mathematician Aryabhata.
• The House of Wisdom used Chinese papermaking technology to create paper versions to be studied and shared.

Q. The student wants to explain how the House of Wisdom preserved the world’s knowledge. Which choice most effectively uses relevant information from the notes to accomplish this goal?
(a) The House of Wisdom was known for bringing together knowledge from around the world, including from Greece, India, and China.
(b) Founded in Iraq in the eighth century, the House of Wisdom employed many scholars as translators.
(c) Writings from the Greek philosopher Aristotle and the Indian mathematician Aryabhata were preserved at the House of Wisdom.
(d) The House of Wisdom collected writings from different countries and created paper versions in Arabic to be studied and shared.
Ans: (d)

• Choice D is the best answer. The sentence explains how the House of Wisdom preserved the world’s knowledge, noting that the library collected, translated, and printed writings from different countries.
• Choice A is incorrect. While the sentence indicates that the House of Wisdom was known for bringing together knowledge from around the world, it doesn’t explain how the library preserved this knowledge.
• Choice B is incorrect. The sentence makes a generalization about the scholars who were employed by the House of Wisdom; it doesn’t explain how the library preserved the world’s knowledge.
• Choice C is incorrect. The sentence identifies two authors whose writings were preserved at the House of Wisdom; it doesn’t explain how the library preserved the world’s knowledge.

Q30: Passage
While researching a topic, a student has taken the following notes:

• British musicians John Lennon and Paul McCartney shared writing credit for numerous Beatles songs.
• Many Lennon-McCartney songs were actually written by either Lennon or McCartney, not by both.
• The exact authorship of specific parts of many Beatles songs, such as the verse for “In My Life,” is disputed.
• Mark Glickman, Jason Brown, and Ryan Song used statistical methods to analyze the musical content of Beatles songs.
• They concluded that there is 18.9% probability that McCartney wrote the verse for “In My Life,” stating that the verse is “consistent with Lennon’s songwriting style.”

Q. The student wants to make a generalization about the kind of study conducted by Glickman, Brown, and Song. Which choice most effectively uses relevant information from the notes to accomplish this goal?
(a) Based on statistical analysis, Glickman, Brown, and Song claim that John Lennon wrote the verse of “In My Life.”
(b) There is only an 18.9% probability that Paul McCartney wrote the verse for “In My Life”; John Lennon is the more likely author.
(c) It is likely that John Lennon, not Paul McCartney, wrote the verse for “In My Life.”
(d) Researchers have used statistical methods to address questions of authorship within the field of music.
Ans: (d)

• Choice D is the best answer. The sentence uses information from the notes to make a generalization about the kind of study Glickman, Brown, and Song conducted. Specifically, the sentence indicates that the study was of a kind that used statistical methods to address questions of authorship within the field of music.
• Choice A is incorrect because the sentence summarizes the methodology and findings of a particular analysis of a single song; it doesn’t make a generalization about the kind of study conducted.
• Choice B is incorrect because the sentence mentions the data and conclusion of a particular analysis of a single song; it doesn’t make a generalization about the kind of study conducted.
• Choice C is incorrect because the sentence focuses on a specific conclusion from a particular analysis of a single song; it doesn’t make a generalization about the kind of study conducted.