天山-4-13

不知道该怎么把题贴过来，快考了（下礼拜一），没时间了

请问此题答案该怎么理解？我选C.

Q13:

Certain genetically modified strains of maize produce a powerful natural insecticide. The insecticide occurs throughout the plant, including its pollen. Maize pollen is dispersed by the wind and frequently blows onto milkweed plants that grow near maize fields. Caterpillars of monarch butterflies feed exclusively on milkweed leaves. When these caterpillars are fed milkweed leaves dusted with pollen from modified maize plants, they die. Therefore, by using genetically modified maize, farmers put monarch butterflies at risk.

Which of the following would it be most useful to determine in order to evaluate the argument?

A. Whether the natural insecticide is as effective against maize-eating insects as commercial insecticides typically used on maize are

B.   Whether the pollen of genetically modified maize contains as much insecticide as other parts of these plants

C.   Whether monarch butterfly caterpillars are actively feeding during the part of the
growing season when maize is releasing pollen

D. Whether insects that feed on genetically modified maize plants are likely to be
killed by insecticide from the plant’s pollen

E.   Whether any maize-eating insects compete with monarch caterpillars for the

           leaves of milkweed plants growing near maize fields

偶也选 C.

  当有花粉时，蝴蝶不吃，那么就不会食物中毒了么。呵呵~

Jeo把题先做成word版，然后就可以贴了。

怎么做???

到下面這個貼子下載沒有保護的天山PDF檔,直接在PDF reader裏就可以copy和past到word裏了...http://forum.chasedream.com/dispbbs.asp?BoardID=22&ID=88491

我认为是E, C选择说: 是否那个毛虫在那个季节" actively" 吃. 注意"actively", 积极的吃, 如果取非,为:不是积极的吃,但还有可能吃, 所以,C并不能起到削弱作用.

E: 是否有其它的虫子和他竞争, 有的话,很好的一个他因削弱, 没有的话,起到加强作用

继续讨论

我也想問E... 我看到C的時候認為C對, 再看下去覺得E也對, 匆匆忙忙就把C給忘了, 選了E...

可是E為什麼不對呢???