What Is Required for Congress to Override a Presidential Veto

What is required for Congress to override a presidential veto?

A) a majority of both houses of Congress
B) two-thirds of both houses of Congress
C) three-fourths of both houses of Congress
D) a unanimous vote of both houses of Congress
E) a president's veto cannot be overridden unless it concerns the budget, in which case it requires a three-fourths of both houses