Gerrymandering is unfair because
a. no one has the right to divide electoral districts for elections.
b. it sets district boundaries to decrease one group's voting strength.
c. it makes voter registration difficult for uneducated white males.
d. it increases the voting power of minority groups.

Gerrymandering is the activity that influences the  outcome of the election without changing how people vote: it only changes how the votes are calculated.

It typically gives the votes of the minority in a given place more influence, so the correct answer is:
d. it increases the voting power of minority groups.

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