(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
原文意思：不想一种青蛙，另外一种青蛙得花三到四年才能成熟，并且这种青蛙只能在深水里面呆着
题目分析：根据unlike frog我们就知道后面应该以frog开头，ABC先干掉。DE进行比较，这两个选项最大的区别就是they这个代词出现的位置，一个先说，一个在逗号后面说，逗号前面是一个完整的意思，reach和take两个动词的发起者都是frogs，没有必要加they，否则就是英吉不仅杀人而且他放火了。而后面restriced是一个独立的意思，如果不加they，动词发起者就不明确了，所以they应该放在逗号后面，选E。
