The correct answer to who can propose an amendment to the Constitution is option D: a two-thirds majority of Congress. Amendments must be proposed either by a two-thirds vote in both houses of Congress or through a Constitutional Convention. The President and the Supreme Court do not have the authority to propose amendments.
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Amendments to the Constitution can only be proposed by a two-thirds majority of Congress. The President and the Supreme Court do not have the authority to propose amendments. Therefore, option OD is correct. ;