Sentence Correction (SC) | Re: Unfortunately, some citizens, unsure whether their votes can influence

IMO E.

Split: Whether VS If.
Whether - used when you have different outcomes.
If - used when there is a condition.

In the given sentence, we have "votes can influence major decisions" - this has 2 outcomes can influence or cannot influence.
So, we should use "whether" here.
Thiseliminates option B.

When "whether is used, using "or not" is unnecessary as it is implied. Thiseliminates C and D.

"some citizens" needs "abstain". We can eliminate
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