How does the Supremacy Clause affect US judges?

How does the Supremacy Clause affect US judges?
A. The Supremacy Clause states that judges can amend state laws.
B. The Supremacy Clause states that no judge can contradict federal laws.
C. The Supremacy Clause states that judges can amend federal laws.
D. The Supremacy Clause states that no judge can contradict state laws.