What is the primary duty of the Vice President?

The primary duty of the Vice President is to support the President and preside over the Senate. This role is significant because it positions the Vice President as both a key advisor and a presiding officer in the legislative branch. The Vice President's involvement in the Senate allows for participation in vital discussions and decisions, including casting tie-breaking votes when necessary.

While the Vice President serves as an advisor to the President, that is a supportive role and not the primary responsibility. Leading the House of Representatives is not within the Vice President's purview, as this role belongs to the Speaker of the House. Additionally, representation in foreign affairs is primarily a responsibility of the President, with the Vice President playing a supportive role in diplomacy but not being the primary representative. Thus, the combination of supporting the President and overseeing Senate operations encapsulates the Vice President's most important duties.