Who becomes President if the current President can no longer serve?

The Vice President is the correct answer because the United States Constitution explicitly outlines the line of succession for the presidency. If the sitting President is unable to continue serving due to reasons such as death, resignation, removal from office, or incapacitation, the Vice President automatically ascends to the presidency. This process ensures continuity of governance and is established under the Presidential Succession Act.

The roles of Secretary of State, Speaker of the House, and Chief Justice do not include the direct responsibility to assume the presidency immediately upon the current President's inability to serve. While these positions are significant in government, they fall further down the line of succession, which prioritizes the Vice President first to maintain a clear and established chain of command.