A state law clashes with a federal law that sits within the national government's constitutional authority. Which law prevails?

1. The supremacy clause in Article VI declares the Constitution and federal law the supreme law of the land. 2. When a state law clashes with a valid federal law, the federal law prevails. 3. The point is that one body of laws binds the whole country, not that states lose every argument. 4. The age of a law plays no part in the rule, so the newer-law and older-law options are traps. _Source: OpenStax American Government 3e (CC BY 4.0), Ch 3 "American Federalism", section 3.1 The Division of Powers_