大全-Section18-11

It is an oversimplified view of cattle raising to say that all one has to do with cattle is leave them alone while they feed themselves, corral them, and to drive them to market when the time is ripe.

(A) all one has to do with cattle is leave them alone while they feed themselves, corral them, and to

(B) all one has to do with cattle is to leave them alone to feed themselves, to corral them, and

(C) all one has to do with cattle is leave them alone while they feed themselves and then corral them and

(D) the only thing that has to be done with cattle is leave them alone while they feed themselves, corral them, and（C）

(E) the only thing that has to be done with cattle is to leave them alone while they feed themselves, to corral them, and

为什么C中间不用to leave them?我觉得答案都不大好。选最好的也应该选E呀。

请高手指点，谢谢。

E的to结构在and后缺乏平行，而且E的表达显然过于繁琐；

C的特点在于，将平行的to结构全部省略，当然更舒适的表达或许是：to leave ... to corral ... and to drive，但是在all结构中，to是可以被全部省略保持平行的。