Which individual is responsible for vetoing bills?

The correct answer identifies the President as the individual responsible for vetoing bills. In the context of the legislative process in the United States, the President has the constitutional authority to reject legislation passed by Congress. When a bill is sent to the President, they can either sign it into law or issue a veto, which sends the bill back to Congress along with their objections.

This power is significant because it allows the President to influence legislation and requires a supermajority in Congress to override a veto, thus ensuring that only those laws that have substantial support can be enacted despite the President's opposition. The mechanisms and checks and balances inherent in this process reflect the separation of powers that is foundational to the U.S. government.

In contrast, the other positions listed do not have the authority to veto bills. The Senate Majority Leader and the Speaker of the House are leaders in their respective chambers of Congress, primarily responsible for guiding legislation through their bodies and setting agendas. The Attorney General oversees the legal affairs of the state or federal government, but does not play a role in the legislative process regarding vetoing bills. Hence, the President stands out as the sole entity with the explicit power to veto legislation.