请教OG-134

atongmu

134. 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 necessary.
(E) Although the enzyme has been synthesized in the laboratory, no large-scale production facilities exist as yet.

我觉得这道题目B比C更加有效而直接的weaken了结论啊。严格的说，甚至可以把C当作无关答案。请大虾们指教。

polarbear223

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?
问题问的是:that go through a caterpillar stage, 所以选C.

atongmu

多谢！

jamesliu79

妙!

pinesong

2楼解释非常巧,我认为答案的意思是b忽视了那些对这种酶有作用的害虫的存在,所以b是有漏洞的,而c并没有说所有害虫都要经过毛虫阶段,但对于经过这个阶段的昆虫,这种喷洒是会杀死益虫的.

summersmile

Choice A is incorrect because spraying, if effective, would make natural predation irrelevant.

是什么意思？哪位nn 帮我分析一下A项？

thx!

wongpaul

这样想: 答案应该是支持这个 SPAYING是无效的. A 说Most species of caterpillar are subject to some natural predation,如果SPAYING 是有效的话,A 依然可以成立,所以A 不是选项!

华籍美人

B是无关选项，OG解释说喷洒不能控制某些害虫并不能说明这种喷洒是不可取的

不要根据常识来判断，而要完全根据题目内容来判断！

我爱欧洲

2楼和8楼的两位MM解释都很棒！两者的意思归根结底是一致的。

richard-ma

这题最关键的地方在“advisable”这个词上面。