Answer:
D. Approving and adopting the U.S. Constitution.
Step-by-step explanation:
A is wrong because ratification means to approve something, not add. B is wrong because making changes had to come after the Constitution was adopted, or, ratified. C is incorrect because voting for a president and vice president is in the process of an election. D is correct because another synonyms for approving and adopting something is called ratification.
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