verbal review - CR

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verbal review - CR

by abhasjha » Sun Sep 28, 2014 5:53 am
Parasitic wasps lay their eggs directly into the eggs of various host insects in exactly the right numbers for any suitable size of host egg, If they laid too many eggs in a host egg, the developing wasp larvae would compete with each other to the death for nutrients and space. If too few eggs were laid, portions of the host egg would decay, killing the wasp larvae.

Which of the following conclusions can properly be drawn from the information above?

A. The size of the smallest host egg that a wasp could theoritically parasitize can be determined from the wasp's egg- laying behavior.

B. Host insects lack any effective defenses against the form of predation practiced by parasitic wasps.

C. Parasitic wasps learn from experience how many eggs to lay into the eggs of different host species.

D. Failure to lay enough eggs would lead to the death of the developing wasp larvae more quickly than would laying too many eggs.

E. Parasitic wasps use visual clues to calculate the size of a host egg.

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by David@GMATPrepNow » Sun Sep 28, 2014 10:34 am
Hi abhasjha,

In this question, we're asked to find the correct conclusion among the answer choices. That means that the correct answer choice is the one that must always be true given the information in the passage. The correct answer is A. Let's take a look at all the answer choices:

A. The size of the smallest host egg that a wasp could theoretically parasitize can be determined from the wasp's egg-laying behavior.

This is true. The wasps lay their eggs directly into the eggs of host insects in the right quantity for any size of host egg. The passage says the host egg must be the right size, which implies that not all egg sizes are right. Therefore the right size can indeed be determined from the wasp's egg-laying behavior.

B. Host insects lack any effective defenses against the form of predation practiced by parasitic wasps.

Whether this is true or not is irrelevant because it is outside the scope of the passage. Eliminate B.

C. Parasitic wasps learn from experience how many eggs to lay into the eggs of different host species.

This is also out of scope. The passage says that the wasps lay the proper number of eggs, but does not explain that this is done from experience. In all probability, if a wasp is laying eggs all over the place, it is not hanging around to see whether or not it got the number right! Eliminate C.

D. Failure to lay enough eggs would lead to the death of the developing wasp larvae more quickly than would laying too many eggs.

The passage does not provide any information about not laying enough eggs. Eliminate D.

E. Parasitic wasps use visual clues to calculate the size of a host egg.

This is also outside the scope of the passage. We are not told how the wasps calculate the size of a host egg. Eliminate E.

I hope this helps!