Which amendment emphasizes the rights of states?

The 10th Amendment to the United States Constitution emphasizes the rights of states by affirming that any powers not delegated to the federal government by the Constitution, nor prohibited to the states, are reserved to the states or to the people. This amendment was adopted as part of the Bill of Rights to ensure that the federal government would not overstep its bounds and encroach on the powers of individual states. It serves as a foundational principle for federalism in the U.S. political system, reinforcing the idea that states have their own rights and powers independent of federal authority.

Other amendments in the list, such as the 3rd, 1st, and 5th, focus on individual rights and liberties, the separation of church and state, freedom of speech, and due process, respectively, and do not specifically address the rights of states. Therefore, the 10th Amendment is the one that explicitly underscores the authority of states within the framework of the Constitution.