Who acts as the President of the Senate?

The Vice President of the United States serves as the President of the Senate. This role primarily involves overseeing the Senate's sessions and ensuring that the rules are followed during debates. The Vice President has the authority to cast a tie-breaking vote when the Senate is evenly divided on legislation. While the Vice President’s role in the Senate is largely ceremonial, it is significant in maintaining the order and functionality of the legislative process.

In contrast, the Speaker of the House presides over the House of Representatives, and the Majority Leader is a key player in guiding the legislative agenda within their respective chamber, but neither has the responsibility for the Senate. The Chief Justice’s role is primarily associated with the judicial branch, specifically overseeing the Supreme Court and presiding over impeachment trials of a president in the Senate, but they do not act as President of the Senate in day-to-day functions. Thus, the Vice President uniquely fulfills the role of President of the Senate, making this choice the correct answer.