大家作一语法题

tongxun

Although it is conceivable that certain electronic devices implanted in the brain may someday correct blindness caused by nerve damage, there is now no clear evidence * of their ability to do it*
A\
B\ of their doing so
C\ that they can do so
D\ that they may one day be able to do so
E\ to do so
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try to find the best answer, although it maybe easy to you.

tongxun

答案：C。E的错误在于：DO的执行者似乎是evidence。

sunny

C的主语应该是they，充当evidence 的同位语从句，对否？

tongxun

不不不！they=devices 。