The achievement of the "great compromise" of the constitutional convention of 1787 was its resolution of the problem regarding

a. women and voting.
b. the definition of citizenship.
c. political representation.
d. states versus federal authority.
e. expansion of slavery into the territories

C. political representation.

Explanation:

The Constitutional Convention took place to decide how the US was going to be governed after the independence from the UK. This is a matter of political representation.

So the correct answer is:

C. political representation.

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