What is an amendment in the context of the Constitution?

An amendment in the context of the Constitution refers specifically to a formal change or addition designed to alter the content of the Constitution itself. This process involves a thorough procedure outlined in Article V of the Constitution, which requires a proposal by either a two-thirds majority in both houses of Congress or by a constitutional convention called for by two-thirds of the state legislatures. Once proposed, an amendment must then be ratified by three-fourths of the state legislatures or by conventions in three-fourths of the states.

This distinguishes amendments from other legislative actions, such as new laws or federal regulations, which do not carry the same constitutional weight or process for enactment. Therefore, option C is the most accurate and precise definition of what an amendment signifies in the realm of constitutional law. Adding or changing provisions in the Constitution has significant implications for governance, which is why such a rigorous procedure is established for amendments.