Which body of Congress must approve presidential nominations?

The Senate is the body of Congress that must approve presidential nominations. This process is outlined in Article II, Section 2 of the Constitution, which states that the President has the power to appoint various officials, including judges, ambassadors, and other high-ranking government positions, but these appointments must receive the "Advice and Consent" of the Senate.

The rationale behind this requirement is to ensure a system of checks and balances, preventing any single branch of government from wielding too much power. By requiring Senate approval, the framers of the Constitution aimed to facilitate cooperation between the executive and legislative branches and to give the Senate a significant role in the appointment process.

This provision does not apply to other bodies mentioned, such as the House of Representatives, which does not have a role in confirming nominations; state legislatures, which handle matters at the state level; or the Supreme Court, which reviews cases and interprets laws rather than participate in the nomination process.