When Ben plays the piano for four hours, and his grade on the math test is 85 percent. Last week, after playing for four hours, Ben considered playing the piano for a fifth hour. He decided to play for one additional hour and cut his study time by one hour, but his math grade fell to 75 percent. What can you conclude about Ben's marginal benefit and marginal cost of the fourth hour of playing the piano? A. The drop of 10 percentage points on a math test exceeded the marginal benefit of a fifth hour of playing the piano. B. The marginal benefit of the fourth hour of playing the piano exceeded the marginal cost of dropping 10 percentage points on a math test. C. The marginal benefit of the fourth hour of playing the piano exceeded its marginal cost. D. The marginal cost of the fourth hour of playing the piano exceeded its marginal benefit