再问大全C-12

handsong

大全-C-12.     Which of the following best completes the passage below?

Monarch butterflies, whose average life span is nine months, migrate from the midwestern United States to selected forests outside Mexico City. It takes at least three generations of monarchs to make the journey, so the great-great-grandchildren who finally arrive in the Mexican forests have never been there before. Yet they return to the same trees their forebears left. Scientists theorize that monarchs, like homing pigeons, map their routes according to the earth’s electromagnetic fields. As a first step in testing this theory, lepidopterists plan to install a low-voltage transmitter inside one grove of “butterfly trees” in the Mexican forests. If the butterflies are either especially attracted to the grove with the transmitter or especially repelled by it, lepidopterists will have evidence that______

(A) monarch butterflies have brains, however minuscule

(B) monarch butterflies are sensitive to electricity

(C) low-voltage electricity can affect butterflies, whether positively or adversely

(D) monarchs map their routes according to the earth’s electromagnetic fields（B）

(E) monarchs communicate in intergenerationally via electromagnetic fields

此题焦点在B和C两个选项，前人的帖子已经讨论不少，公认的看法是C错在butterflies之前没有加monarch进行限定。

可是，如果这个道理成立的话，B中的electricity就是极大错误！因为electricity可以是几伏的低电压(如文中所用设备产生的电压)，也可以是几千伏的高电压，如不对这个electricity进行限定，那整个意思就差太远了。

我认为还是选C，因为文中指出了是low-voltage transmitter，所以必须用low-voltage electricity 对应，至于butterflies的修饰，其实文中最后一句也只用了the butterflies，所以C中的butterflies对应文中的butterflies 问题不大，当然butterflies之前加个the是最好。

望大家讨论。

handsong

大家帮忙看看！

handsong

顶！

handsong

没人理？