The true statement about the amendment process is:
Both the national government and the states are involved.
The amendment process, as outlined in Article V of the U.S. Constitution, requires proposals to be made by either a two-thirds majority in both the House of Representatives and the Senate or by a national convention called by two-thirds of the state legislatures. Amendments are then ratified by three-fourths of the state legislatures or by conventions in three-fourths of the states, thus involving both the national government and the states.