Inferences Flashcards
Volunteering, or giving time for a community service for free, is a valuable form of civic engagement because helping in acommunity is also good for society as a whole. In a survey of youths in the United States, most young people said that theybelieve volunteering is a way to help people on an individual level. Meanwhile, only 6% of the youths said that they thinkvolunteering is a way to help fi x problems in society overall. These replies suggest that ______
Which choice most logically completes the text?
A.
many young people think they can volunteer only within their own communities.
B.
volunteering may be even more helpful than many young people think it is.
C.
volunteering can help society overall more than it can help individual people.
D.
many young people may not know how to fi nd ways to volunteer their time.
B
Mosses can struggle in harsh desert conditions because these plants require enough sunlight for photosynthesis but not somuch that they risk drying out. Researchers Jenna Ekwealor and Kirsten M. Fisher found several species of
Syntrichiacaninervis
, a type of desert moss, growing under quartz crystals in California’s Mojave Desert. To evaluate whether thesesemitransparent rocks benefi ted the moss, the researchers compared the shoot tissue, a measure of plant growth, of
S.caninervis
when growing on the soil surface versus when the moss was growing under the quartz rocks. They found thatthe shoot tissue was 62% longer for moss growing under the quartz as compared to moss on the soil surface, suggestingthat ______
Which choice most logically completes the text?
A.
S. caninervis
is one of the few types of moss that can survive under semitransparent rocks.
B.
quartz crystals do not transmit the necessary sunlight for photosynthesis in
S. caninervis
.
C.
S. caninervis
growing under quartz crystals experience lower light intensity and are thus able to retain more moisture.
D.
quartz crystals are capable of supporting
S. caninervis
growth if the crystals are not too thin.
C
Scientists studying Mars long thought the history of its crust was relatively simple. One reason for this is that geologic andclimate data collected by a spacecraft showed that the crust was largely composed of basalt, likely as a result of intensevolcanic activity that brought about a magma ocean, which then cooled to form the planet’s surface. A study led by ValeriePayré focused on additional information—further analysis of data collected by the spacecraft and infrared wavelengthsdetected from Mars’s surface—that revealed the presence of surprisingly high concentrations of silica in certain regions onMars. Since a planetary surface that formed in a mostly basaltic environment would be unlikely to contain large amounts ofsilica, Payré concluded that ______
Which choice most logically completes the text?
A.
the information about silica concentrations collected by the spacecraft is likely more reliable than the silica informationgleaned from infrared wavelengths detected from Mars’s surface.
B.
high silica concentrations on Mars likely formed from a different process than that which formed the crusts of otherplanets.
C.
having a clearer understanding of the composition of Mars’s crust and the processes by which it formed will providemore insight into how Earth’s crust formed.
D.
Mars’s crust likely formed as a result of other major geological events in addition to the cooling of a magma ocean.
D
If some artifacts recovered from excavations of the settlement of Kuulo Kataa, in modern Ghana, date from the thirteenthcentury CE, that may lend credence to claims that the settlement was founded before or around that time. There is otherevidence, however, strongly supporting a fourteenth century CE founding date for Kuulo Kataa. If both the artifact dates andthe fourteenth century CE founding date are correct, that would imply that ______
Which choice most logically completes the text?
A.
artifacts from the fourteenth century CE are more commonly recovered than are artifacts from the thirteenth centuryCE.
B.
the artifacts originated elsewhere and eventually reached Kuulo Kataa through trade or migration.
C.
Kuulo Kataa was founded by people from a different region than had previously been assumed.
D.
excavations at Kuulo Kataa may have inadvertently damaged some artifacts dating to the fourteenth century CE
B
Geoglyphs are large-scale designs of lines or shapes created in a natural landscape. The Nazca Lines were created in theNazca Desert in Peru by several Indigenous civilizations over a period of many centuries. Peruvian archaeologist Johny Islaspecializes in these geoglyphs. At a German exhibit about the Nazca Lines, he saw an old photograph of a large geoglyph ofa whalelike fi gure and was surprised that he didn’t recognize it. Isla returned to Peru and used a drone to search a widearea, looking for the fi gure from the air. This approach suggests that Isla thought that if he hadn’t already seen it, thewhalelike geoglyph ______
Which choice most logically completes the text?
A.
must represent a species of whale that went extinct before there were any people in Peru.
B.
is actually located in Germany, not Peru, and isn’t part of the Nazca Lines at all.
C.
is probably in a location Isla hadn’t ever come across while on the ground.
D.
was almost certainly created a long time after the other Nazca Lines geoglyphs were created
C
During the Bourbon Restoration in France (1814–1830), the right to vote required in part that a person paid at least 300francs in direct taxes to the government. The four most common taxes (the
quatre vieilles
) were levied on real estate (bothland and buildings); the doors and windows in taxpayer homes; the rental values of homes; and the businesses of artisansand merchants. (Foreign investments were either exempt from taxation or taxed lightly.) Although relatively few people paidthe tax on real estate, it was the main means of voter qualifi cation and accounted for over two-thirds of governmentreceipts during this period, suggesting that during the Bourbon Restoration ______
Which choice most logically completes the text?
A.
those people who had the right to vote most likely had substantial holdings of French real estate.
B.
the voting habits of French artisans and merchants were effective in reducing tax burdens on businesses.
C.
the number of doors and windows in French residences was kept to a minimum but increased after 1830.
D.
French people with signifi cant foreign investments were unlikely to have the right to vote.
A
The domestic sweet potato (
Ipomoea batatas
) descends from a wild plant native to South America. It also populates thePolynesian Islands, where evidence confi rms that Native Hawaiians and other Indigenous peoples were cultivating the plantcenturies before seafaring fi rst occurred over the thousands of miles of ocean separating them from South America. Toexplain how the sweet potato was fi rst introduced in Polynesia, botanist Pablo Muñoz-Rodríguez and colleagues analyzedthe DNA of numerous varieties of the plant, concluding that Polynesian varieties diverged from South American ones over100,000 years ago. Given that Polynesia was peopled only in the last three thousand years, the team concluded that ______
Which choice most logically completes the text?
A.
the cultivation of the sweet potato
in Polynesia likely predates its cultivation in South America.
B.
Polynesian peoples likely acquired the sweet potato from South American peoples only within the last three thousandyears.
C.
human activity likely played no role in the introduction of the sweet potato in Polynesia.
D.
Polynesian sweet potato varieties likely descend from a single South American variety that was domesticated, not wild.
C
Ratifi ed by more than 90 countries, the Nagoya Protocol is an international agreement ensuring that Indigenouscommunities are compensated when their agricultural resources and knowledge of wild plants and animals are utilized byagricultural corporations. However, the protocol has shortcomings. For example, it allows corporations to insist that theiragreements with communities to conduct research on the commercial uses of the communities’ resources and knowledgeremain confi dential. Therefore, some Indigenous advocates express concern that the protocol may have the unintendedeffect of ______
Which choice most logically completes the text?
A.
diminishing the monetary reward that corporations might derive from their agreements with Indigenous communities.
B.
limiting the research that corporations conduct on the resources of the Indigenous communities with which they havesigned agreements.
C.
preventing independent observers from determining whether the agreements guarantee equitable compensation forIndigenous communities.
D.
discouraging Indigenous communities from learning new methods for harvesting plants and animals from theircorporate partners.
C
Some
Astyanax mexicanus
, a river-dwelling fi sh found in northeast Mexico, have colonized caves in the region. Althoughthere is little genetic difference between river and cave
A. mexicanus
and all members of the species can emit the samesounds, biologist Carole Hyacinthe and colleagues found that the context and signifi cance of those sounds vary by location—e.g., the click that river-dwelling
A. mexicanus
use to signal aggression is used by cave dwellers when foraging—and theacoustic properties of cave fi sh sounds show some cave-specifi c variations as well. Hyacinthe and colleagues note thatdifferences in sonic communication could accumulate to the point of inhibiting interbreeding among fi sh from differentlocations, suggesting that ______
Which choice most logically completes the text?
A.
although
A. mexicanus
living in rivers are genetically similar to those living in caves, river fi sh rely on soniccommunication less than cave fi sh do.
B.
although
A. mexicanus
is a single species at present, it could be in the process of splitting into distinct populations withdifferent characteristics.
C.
although all
A. mexicanus
emit sounds, the fi sh living in rivers produce some sounds that the fi sh living in caves do not,and vice versa.
D.
although
A. mexicanus
from different locations can interbreed currently, river fi sh and cave fi sh are suffi cientlygenetically distinct that they can be considered separate species.
B
German theater practitioner Bertolt Brecht (1898–1956) believed that theater should elicit an intellectual rather than anemotional response from audiences, provoking them to consider social and political realities that extend beyond thecharacters and events depicted onstage. Brecht’s infl uence can be seen in English playwright Caryl Churchill’s 1979 play
Cloud 9
: although the play sometimes invites empathetic reactions, it primarily works to engage audiences in aninterrogation of patriarchy and colonialism, which it does by placing audiences at a distance, thereby encouraging them to
______
Which choice most logically completes the text?
A.
focus on the characters’ beliefs about social and political issues as revealed by the characters’ actions.
B.
refl ect on social and political phenomena not directly related to patriarchy and colonialism.
C.
recognize pertinent social and political parallels between Germany during Brecht’s time and England at the time whenChurchill was writing
Cloud 9
.
D.
be dispassionate as they think critically about the social and political questions raised by the play.
D
One challenge when researching whether holding elected offi ce changes a person’s behavior is the problem of ensuring thatthe experiment has an appropriate control group. To reveal the effect of holding offi ce, researchers must compare peoplewho hold elected offi ce with people who do not hold offi ce but who are otherwise similar to the offi ce-holders. Sinceresearchers are unable to control which politicians win elections, they therefore ______
Which choice most logically completes the text?
A.
struggle to fi nd valid data about the behavior of politicians who do not currently hold offi ce.
B.
can only conduct valid studies with people who have previously held offi ce rather than people who presently hold offi ce.
C.
should select a control group of people who differ from offi ce holders in several signifi cant ways.
D.
will fi nd it diffi cult to identify a group of people who can function as an appropriate control group for their studies.
D
Archaeologists and historians used to believe that the Maya civilization during its Classic period (roughly 250–900) lackedagricultural marketplaces. One reason for this belief was that these scholars misunderstood the ecology of the regions theMaya inhabited. Marketplaces typically emerge because different individuals or groups want to trade resources they controlfor resources they don’t control. Scholars seriously underestimated the ecological diversity of the Maya landscape and thusassumed that ______
Which choice most logically completes the text?
A.
marketplaces likely would not have attracted many traders from outside the regions controlled by the Maya.
B.
farming practices would have been largely the same throughout Maya lands even if the crops people produced variedsignifi cantly.
C.
marketplaces would not have enabled Maya people to acquire many products different from those they alreadyproduced.
D.
farmers would trade agricultural products only if they had already produced enough to meet their own needs.
C
In a study of the cognitive abilities of white-faced capuchin monkeys (
Cebus imitator
), researchers neglected to control forthe physical diffi culty of the tasks they used to evaluate the monkeys. The cognitive abilities of monkeys given problemsrequiring little dexterity, such as sliding a panel to retrieve food, were judged by the same criteria as were those of monkeysgiven physically demanding problems, such as unscrewing a bottle and inserting a straw. The results of the study, therefore,
______
Which choice most logically completes the text?
A.
could suggest that there are differences in cognitive ability among the monkeys even though such differences may notactually exist.
B.
are useful for identifying tasks that the monkeys lack the cognitive capacity to perform but not for identifying tasks thatthe monkeys can perform.
C.
should not be taken as indicative of the cognitive abilities of any monkey species other than
C. imitator
.
D.
reveal more about the monkeys’ cognitive abilities when solving artifi cial problems than when solving problemsencountered in the wild.
A
One theory behind human bipedalism speculates that it originated in a mostly ground-based ancestor that practiced four-legged “knuckle-walking,” like chimpanzees and gorillas do today, and eventually evolved into moving upright on two legs.But recently, researchers observed orangutans, another relative of humans, standing on two legs on tree branches andusing their arms for balance while they reached for fruits. These observations may suggest that ______
Which choice most logically completes the text?
A.
bipedalism evolved because it was advantageous to a tree-dwelling ancestor of humans.
B.
bipedalism must have evolved simultaneously with knuckle-walking and tree-climbing.
C.
moving between the ground and the trees would have been diffi cult without bipedalism.
D.
a knuckle-walking human ancestor could have easily moved bipedally in trees.
A
Tides can deposit large quantities of dead vegetation within a salt marsh, smothering healthy plants and leaving a saltpanne—a depression devoid of plants that tends to trap standing water—in the marsh’s interior. Ecologist Kathryn Beheshtiand colleagues found that burrowing crabs living within these pannes improve drainage by loosening the soil, leading thepannes to shrink as marsh plants move back in. At salt marsh edges, however, crab-induced soil loosening can promotemarsh loss by accelerating erosion, suggesting that the burrowing action of crabs ______
Which choice most logically completes the text?
A.
can be benefi cial to marshes with small pannes but can be harmful to marshes with large pannes.
B.
may promote increases in marsh plants or decreases in marsh plants, depending on the crabs’ location.
C.
tends to be more heavily concentrated in areas of marsh interiors with standing water than at marsh edges.
D.
varies in intensity depending on the size of the panne relative to the size of the surrounding marsh.
B