There is something weird about this topic. There is no convincing explanation to why the company claims C to be the right choice. It is clear tht Hillary is the one who did the action of climbing, and so he should occupy the post of the subject, whatever be the voice, passive or active. Therefore, D is the only plausible answer IMO. . I am not able to see the explanation why the company feels C as the right choice, in spite off the great mis – modification. Will this stand as the GMAT-fit question?
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