Sentence Correction (SC) | Re: While many citizens feel powerless to influence national policy, it is

Not sure whether this question is much GMAT-like. In the OA (option B), the parallelism between the two clauses are not maintained. Ideally the structure should be:

While X does...., Y does.....

A more GMAT-like construction could be:
While many citizens feel powerless to influence national policy, some believe that writing to a Congressperson with an opinion is effective.

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