What action is an example of a power denied by the states?

Conducting foreign affairs is an action that exemplifies a power denied to the states because the Constitution specifically grants this authority to the federal government. The framers of the Constitution designed it this way to ensure a unified national policy in matters of foreign relations, thereby preventing individual states from pursuing their own foreign policies or treaties, which could lead to conflicts and inconsistencies.

In contrast, establishing local governments, levelling taxes, and issuing driver's licenses are powers that states retain and can exercise. States have the authority to create local governments to manage local affairs, implement tax policies to fund state and local programs, and regulate matters such as issuing driver's licenses to maintain control over transportation and public safety within their jurisdictions.