The basic principle of popular sovereignty refers to the idea that the authority of the government is derived from the consent of the governed. In other words, the power of the government is established and maintained by the will of the people. This principle underscores that the people have the right to make decisions regarding their governance, including the right to alter or abolish their government if it fails to serve their interests.
Among the options provided, "The people have the right to alter their government" aligns most closely with the concept of popular sovereignty.