Final answer:
The process to amend the Constitution is two-fold: Proposal by either Congress with a two-thirds vote or a convention called by two-thirds of states, followed by Ratification by three-fourths of the state legislatures.
Step-by-step explanation:
The process an amendment must follow to become a part of the Constitution involves two key steps: Proposal and Ratification. Firstly, to propose an amendment, either two-thirds of both chambers of Congress must agree, or two-thirds of the states can call for a convention to propose an amendment. Secondly, ratifying the amendment requires the approval of three-fourths of the state legislatures. The correct sequence for the amendment process, based on the information provided, is reflected in option 2: Proposal, Approval by Congress, and Ratification by the States. It is important to highlight that this process does not involve the President's approval; the amendment goes directly from Congress to the states for ratification.