GMAT Sentence Correction (SC) | Re: The human nervous system and a telephone system superficially resemble

I would go with C. Obviously 'Not only ' is a flawed sentence as we do not have a 'but also' twin completing the sentence (non-underlined). So, we can eliminate A and E. Changing the decision point now, the sentence D, has a minor change in meaning (According to me!). Hence B and D remain. I prefer C because both the reasons talk about why the Nervous system resembles the telephone system rather than using "they" as in B.

So, C.

OA awaited. thanks, get to stumble alot on your posts.
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