PREP的一道题，实在想不通

xihongshi7_7

Unlike frogs that metamorphose from tadpoles into adults within a one-year period, it takes three to four years for the mountain yellow-legged frog of the Sierra Nevada to reach adulthood, and so they are restricted to deeper bodies of water that do not dry up in summer or freeze solid in winter.

 (A) it takes three to four years for the mountain yellow-legged frog of the Sierra Nevada to reach adulthood, and so they are

 (A) it takes three to four years for the mountain yellow-legged frog of the Sierra Nevada to reach adulthood, and so they are

(B) it takes the mountain yellow-legged frog of the Sierra Nevada three to four years until it reaches adulthood, and therefore it is

(C) in the Sierra Nevada, mountain yellow-legged tree frogs take three to four years to reach adulthood, thus being

(D) mountain yellow-legged frogs of the Sierra Nevada take three to four years until they reach adulthood, thus

(E) mountain yellow-legged frogs of the Sierra Nevada take three to four years to reach adulthood, and so they are

C为什么不对呢，答案是E

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这个狠明显不能选C,

根据平行原则,青蛙只能和青蛙平行

答案在DE之间选择

？？青蛙和青蛙平行，C是符合的，Unlike frogs....., in the Sierra Nevada, mountain yellow-legged tree frogs........;另外thus being 更表明后面是结果状语了。所以我觉得还是不能排除C。

按照那个原则,"当绝对排除A的前提下,找和A近的那个选项"

那就是E了.

仔细看也还是E,因为take... to...,是个词组啊, 只是第一个空里面填写了(3-4 years)

后半句,狠明显2个句子因果关系,但是thus只能当副词,不能连接句子,所以一定要有and的帮助,故而D错了