Which of the following is NOT a power of the Legislative branch?

Making treaties is generally considered to be a power that is shared between the Legislative branch and the Executive branch, specifically with the President. While the Legislative branch, particularly the Senate, must provide advice and consent on treaties negotiated by the President, the actual power to negotiate treaties lies primarily with the Executive. This means that while the Senate plays a crucial role in the process, it does not independently have the power to make treaties without the cooperation of the Executive branch.

In contrast, declaring war, coining money, and collecting taxes are powers that are explicitly outlined in the Constitution as responsibilities of the Legislative branch. Congress has the authority to declare war, which involves the decision to engage in military conflict. Similarly, Congress holds the power to coin money and regulate its value, as well as to levy taxes to provide for the federal government's operations. These responsibilities demonstrate the essential role of Congress in managing the nation's fiscal and military affairs.