Under laboratory conditions, fruit flies can learn (2)

Question

Under laboratory conditions, fruit flies can learn to respond to odors that elicit no response from them in nature. Mutant fruit flies that cannot produce a certain enzyme are, however, incapable of such learning. These mutant flies respond to other odors just as ordinary fruit flies do. Thus it is unlikely that the enzyme's absence impairs the fruit flies' perception of odors, since presumably,  fruit flies would not have an enzyme that was needed only for the perception of odors that fruit flies do not respond to in nature . Instead, what the enzyme's absence probably impairs is the fruit flies' ability to learn, since  many researchers believe that this enzyme is somehow involved in the process of forming memories .

In the argument given, the two  boldfaced  portions play which of the following roles?

A. The first is evidence that has been used to corroborate a judgment that the argument contends is false; the second is that judgment.

B. The first is a hypothesis that the argument opposes; the second is a judgment that has been advanced in support of that hypothesis.

C. The first is the hypothesis that the argument as a whole seeks to establish; the second provides support for that hypothesis.

D. The first presents an explicit assumption that is introduced in arguing for the position that the argument adopts; the second provides evidence to support that position.

E. The first offers justification for an assumption that is explicitly made in the argument; the second states that assumption.

Bunuel · Answer

Discussed here: https://gmatclub.com/forum/under-laboratory-conditions-fruit-flies-can-learn-to-respond-to-odors-414689.html

VerbalBot · Answer

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Under laboratory conditions, fruit flies can learn (2)

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