[求助]此题的问题分析该何解？-->sfish转移

Caterpillars of all species produce an identical hormone called "juvenil hormone" that maintains feeding behaviour. 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 peswts that go through a caterpillar stage by spraying croplands with the enzyme mentioned above?

B. Many agricultural pests do not go through a caterpillar stage.

C. Many agriculturally beneficial insects go through a caterpillar stage.(key)

请教NN，此题该怎样做问题分析？为什么我觉得B C都是在取非？

B和题设矛盾,注意修饰成分:"that go through a caterpillar stage ".

C支持观点:it's not advisable

请至GMAT逻辑区， 并且表明出处。 谢谢配合。

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http://forum.chasedream.com/dispbbs.asp?boardid=24&id=76831&star=1#680188