新Prep2-234 无人问过耶！

mimily

我是不是很差劲啊？搜了，竟发现没人问过这题。大家鼓励鼓励我吧。
234.    (28864-!-item-!-188;#058&003290)    (GWD-3-Q28)

The coyote is one of several recent ecological success stories:  along with the white-tailed deer, the moose, and other species that are enlarging their natural domains, they have established themselves as supreme adapters in an era when the capability to adjust to the environmental changes wrought by human beings has created a whole new class of dominant large mammals.
A. they have established themselves as supreme adapters in an era when the capability
B. they have established themselves as being supreme adapters in an era when being able
C. it has established itself as a supreme adapter in an era when to be able
D. it has established itself as being a supreme adapter in an era when its ability
E. it has established itself as a supreme adapter in an era when the ability

我选C，答案是E
我也知道when to do有点奇怪。想问下是否语法上有这条呢？
谢谢

jtrchina

First,in standard written english,"when" is a conjunction that needs its own subject and verb.In this issue,the infinitive,"to be able……",can not be used as a subject.
Second,the underline can be simplified as "when to be able……has created……" .However,"to be able" can not do the action,"has created a new species".
Hope it helps!