Option C is the correct answer because ‘does’ is used for singular third person forms, does not belong means that she is not a part of, so it is correct.
Option D is incorrect because ‘will’ is the future tense, And will not belong means that she probably does belong now, but will not belong to a party later on, which is incorrect.
Option B is incorrect Jill is one person, and ‘have’ is used in plural forms.
Option A is incorrect because ‘is not belonging’ is incorrectly written, it would be correct if it was, “but she isn’t from/ a part of a political party”.