Parasitic wasps propagate by injecting their eggs into a caterpillar that then becomes paralyzed as the eggs inside develop into wasp larvae. The wasp larvae kill the caterpillar host as they feed on it, form cocoons, and finally develop into wasps. In attempting to discover how such wasps detect the presence of the caterpillar hosts that are so critical to the wasps’ propagation, researchers have uncovered an intriguing defense mechanism developed by the plants on which the caterpillars feed.

When chewed on, many plants release volatile compounds from both damaged and undamaged tissues. When these compounds are toxic to the insects that feed on the plants, they can help defend the plants from such attacks. However, the plants on which the wasps’ caterpillar hosts feed have evolved an even more complex defense: the caterpillar-infested plants appear to release volatile chemicals that attract parasitic wasps, which then prey on the caterpillars. Scientists originally suspected that the wasps were attracted by an odor, reminiscent of cut grass, that is released as the caterpillar feeds, but a recent study suggests that a different set of volatile attractants is involved. In this study, when researchers used a razor blade to mimic caterpillar damage on the leaves, only grassy odors were emitted, not the volatile compounds that attracted wasps. However, when oral secretions from the caterpillars were applied to these damaged leaves, the leaves released the wasp attractants several hours later. Further tests revealed that oral secretions placed on the razor-damaged leaves stimulated the release of such attractants, making the plants as attractive to wasps as plants that had suffered actual caterpillar damage. These results suggest that chemicals from the caterpillar must be present for these attractants to be released and that unlike the grassy scent, which emanates only as the caterpillar on the plant, the wasp attractants are produced several hours after the attack and persist for several hours, perhaps days. Researchers have launched additional studies to determine whether the wasps’ capacity to prey on caterpillars can be enhanced to the extent that the wasps could be used as a natural pesticide to "police" plants and protect them from crop-destroying caterpillars.

It can be inferred from the passage that if the leaves of a plant were damaged by wind rather than by caterpillars, the parasitic wasps would

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Parasitic wasps propagate by injecting their eggs into a caterpillar that then becomes paralyzed as the eggs inside develop into wasp larvae. The wasp larvae kill the caterpillar host as they feed on it, form cocoons, and finally develop into wasps. In attempting to discover how such wasps detect the presence of the caterpillar hosts that are so critical to the wasps’ propagation, researchers have uncovered an intriguing defense mechanism developed by the plants on which the caterpillars feed.

When chewed on, many plants release volatile compounds from both damaged and undamaged tissues. When these compounds are toxic to the insects that feed on the plants, they can help defend the plants from such attacks. However, the plants on which the wasps’ caterpillar hosts feed have evolved an even more complex defense: the caterpillar-infested plants appear to release volatile chemicals that attract parasitic wasps, which then prey on the caterpillars. Scientists originally suspected that the wasps were attracted by an odor, reminiscent of cut grass, that is released as the caterpillar feeds, but a recent study suggests that a different set of volatile attractants is involved. In this study, when researchers used a razor blade to mimic caterpillar damage on the leaves, only grassy odors were emitted, not the volatile compounds that attracted wasps. However, when oral secretions from the caterpillars were applied to these damaged leaves, the leaves released the wasp attractants several hours later. Further tests revealed that oral secretions placed on the razor-damaged leaves stimulated the release of such attractants, making the plants as attractive to wasps as plants that had suffered actual caterpillar damage. These results suggest that chemicals from the caterpillar must be present for these attractants to be released and that unlike the grassy scent, which emanates only as the caterpillar feeds on the plant, the wasp attractants are produced several hours after the attack and persist for several hours, perhaps days. Researchers have launched additional studies to determine whether the wasps’ capacity to prey on caterpillars can be enhanced to the extent that the wasps could be used as a natural pesticide to "police" plants and protect them from crop-destroying caterpillars.

The author implies that if, in the experiment described in the second paragraph, the parasitic wasps had been drawn to the plants after they had been damaged by a razor blade but without application of oral secretions from the caterpillar, then scientists would likely have concluded which of the following?

Wasps are attracted to the plants by the grassy odor released as the caterpillars feed on the plants’ leaves.

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The ornithologist interpreted the ravens’ behavior as indicating that they were looking for another bird’s food cache of which it did not know its exact location.

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Purina her lifetime, when her 1922 book Etiquette was running second only to the Bible in United States sales. Emily Post was ridiculed as a period-piece snob focused on minutiae, even though her book argued against snobbery.

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A series of financial reports in recent months has portrayed an economy that is slowing sharply, thus raising expectations that the Federal Reserve v.ill be comp.. -xi to cut interest rates in order to avert a recession.

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Despite his renowned contributions to resolving archaeological questions, he was unable to provide hardly any insight into reconciling the conflicting linguistic and cultural evidence with respect to the expansion of agriculture.

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Manufacturers and retailers tend to look askance at gray markets, where products are sold at cut-rate prices outside their authorized distribution channels. Manufacturers fear that gray markets will undercut margins and tarnish brand names. Retailers fear that they will siphon away customers and erode prices.

A new study indicates, however, that gray marketing actually benefits manufacturers and retailers in markets that meet two criteria: first, sharp differences exist in consumers’ price sensitivity; second, large numbers of consumers are price-insensitive. In such markets, the low prices of the gray market will attract the most price-sensitive customers. The authorized channels will then compete only for the remaining customers―those who are insensitive to price but sensitive to service.

When that happens, the structure of competition and the economics of the market shift. The authorized retailers, freed from having to cater to the bargain hunters, can raise their prices and focus on service. If the concentration of price-insensitive shoppers is high enough, the resulting increase in prices will more than offset the loss of sales to the bargain hunters. The margins and profits of the authorized retailers will increase, and manufacturers will, as a result, be able to boost their wholesale prices.

Which of the following, if true, would most undermine the reasoning offered for the claim that gray markets can in certain conditions lead to increased profits among authorized retailers?

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Members of many primate species approach an opponent shortly after conflict and initiate behaviors such as embracing, grooming, or huddling―a phenomenon researchers call postconflict reconciliation. Existing research, however, suffers from several shortcomings. The variability between groups of the same species is rarely addressed; the majority of studies investigate only a small fraction of the pairings that exist in a given group; and almost all reports are restricted to animals in captivity.

In an attempt to address some of these shortcomings, Sommer et al. recently conducted a study of postconflict reconciliation in wild Hanuman langurs, a species of colobine monkey. They observed rates of postconflict reconciliation much lower than would be expected based on previous research, and found that over 80 percent of all pairings exhibited no postconflict affinity whatsoever. The rarity of friendly postconflict reunion in wild langurs draws attention to the possibility that conflicts are modulated through avoidance. The option of temporarily avoiding contact with opponents is not easily available to captive primates, and certainly not to the extent present in the wild. Still, studies of postconflict behavior of primates in captivity remain valuable: above all, they demonstrate the flexibility of nonhuman primates in various environments. It is likely, however, that the reported frequency of reconciliation among primates is artificially inflated by the conditions of captivity.

Which of the following is a research shortcoming mentioned in the passage that is not addressed in the information provided about Sommer’s study?

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The passage suggests most strongly that in the presence of certain economic conditions, gray markets will encourage authorized retailers to

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Government regulations in Nation X require that milk products labeled "organic" come from cows that have access to pasture. Many industrial dairies have begun using the organic label on their products even though their cows spend most of their milk-bearing lives confined to feed lots eating grain. Critics charge that industrial dairy cows spend too little time grazing in pastures for their milk to bear the organic label, but the cows’ owners insist that the animals are in good health and show no signs of discontent.

Which of the following would it be most useful to establish in order to determine whether the industrial dairies’ use of the organic label complies with government regulations?

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