The Main Reason That American Executives Are Paid So Much

The main reason that American executives are paid so much is:

A) Pay is set by the compensation committees of the board, largely comprised of other CEOs who have an interest in pushing compensation up.
B) Qualified individuals are scarce, because most current CEOs were born during the "baby bust" years of the Great Depression.
C) High executive compensation in other nations puts upward pressure on the salaries of U.S. executives.
D) Most executives are paid based on their performance, and rising compensation reflects the excellent performance of their firms.