Caterpillars of all species produce an identical hormone called "juvenile hormone" that maintains feeding behavior. Only when a caterpillar has grown to the right size for pupation to take place does a special enzyme halt the production of juvenile hormone. This enzyme can be synthesized and will, on being ingested by immature caterpillars, kill them by stopping them from feeding.

Which of the following, if true, most strongly supports the view that it would not be advisable to try to eradicate agricultural pests that go through a caterpillar stage by spraying croplands with the enzyme mentioned above?

A: Most species of caterpillar are subject to some natural predation.
B: Many agricultural pests do not go through a caterpillar stage.
C: Many agriculturally beneficial insects go through a caterpillar stage.
D: Since caterpillars of different species emerge at different times, several sprayings would be neccesary.
E: Although the enzyme has been synthsized in the laboratory, no large-scale production facilities exist as yet.
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Best regards,

B)

C) should be out because it would still be advisable because it would eliminate the pests as well as many beneficial insects but we can assume that there are other beneficial factors so the goal would be achieved.

not B, not C

not B---- because the question stem--

is asking--- "why the spraying of the enzyme is not advisable to kill the pests that go through caterpillar stage"

so in a way B is out of scope.

answere should be between A , D and E

D --seems best as spraying at diff time may result in the development of mature caterpillars-- hence not affected by the enzyme.

1) Caterpillars of all species produce an identical hormone called "juvenile hormone" that maintains feeding behavior.
2) Only when a caterpillar has grown to the right size for pupation to take place does a special enzyme halt the production of juvenile hormone.
3) This enzyme can be synthesized and will, on being ingested by immature caterpillars, kill them by stopping them from feeding.

We'red asked to find a statement that supports the view that it is not advisable to eradicate pests that go through a caterpillar stage by spraying croplands with the enzyme.

A: Most species of caterpillar are subject to some natural predation.
- Out of scope

B: Many agricultural pests do not go through a caterpillar stage.
- If many pests do not go through a caterpilar stage, then there is really no point in spraying the croplands with the enzyme.

C: Many agriculturally beneficial insects go through a caterpillar stage.
- We're more concerned removing the caterpillars (but not via enzyme spraying) than preserving benficial insects.

D: Since caterpillars of different species emerge at different times, several sprayings would be neccesary.
- We're not concerned how many sprays in a year are needed. All we want is an answer choice that tells us why spraying enzymes on the croplands are not advisable.

E: Although the enzyme has been synthsized in the laboratory, no large-scale production facilities exist as yet.
- Out of scope

I'll take B

"C"....we r concerned abt getting rid of few pests that go thro the caterpillar stages...."B" is not it, becose even if many of the paets don't go thro the stages, but we can still achieve our goal to eradicate the ones that do go thro those stages, as we r not out to eradicate all pests. Only C has a bad side effect of spraying.

I would choose C too. Almost chosen B, but on a closer look at the question, it says why it is not advisable to use the enzyme to kill agricultural pests that go through a caterpillar stage.

But it is not asking about those pest that do not go through a catapiller case.

For example, I say "We can't buy a red sweater because they are all too big for me." and you say "But this white sweater is not too big." Well but I'm not talking about white sweaters.

It basically says when catapillars grow up to a certain size, its body will generate certain enzyme that make it stop feeding itself before it makes the little house for itself (then it will become a butterfly). So if we can make the same enzyme and spread it to a young catapillar then it will stop feeding itself, but it's not ready to become a butterfly yet. Instead it will die.

Question asks why it is not good to use this method to kill the agriculture pest that go through the catapillar phases. Well I believe that is because other good insects may also be killed by this method, which is not good.

GMAT will never give you two correct answers for CR questions.

Here's my reason why I chose C.

The best answer is C