You will find what great benefit the computer you own can be each time you use it to help

You will find what great benefit the computer you own can be each time you use it to help you work.
A. for
B. at
C. of
D. on

A. forB. at(答案→)C. ofD. on解析：句意:你将发现你有电脑的最大的利益是每次你可以用它来帮助你工作。这里what引导的是感叹句，正常的语序是You will find the computer you own can be of great benefit each time you use it to help you work.这里被感叹的是名词great benefit，当然great修饰它应和它放在一起，所以of还是放在原来的位置。故选C。

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