Which official is the head of the executive branch?

A. the Chief Justice

B. the Chairman of the Joint Chiefs of Staff

C. the Speaker of the House

D. the president

In the US, the head of the executive branch is the Presitent of the United States. (answer D).

The president is supported in his (so far, maybe in the future: hers) tasks by the vice-president, the Cabinet (the head of the executive departments) and by departments and Institutes,