After Eating Four Slices of Pizza, You Are Offered a Fifth

Multiple Choice

After eating four slices of pizza, you are offered a fifth slice for free. You turn down the fifth slice. Your refusal indicates that the

A) marginal utility for four pizza slices is negative.
B) total utility for five pizza slices is negative.
C) marginal utility is positive for the fourth slice and negative for the fifth slice.
D) marginal utility for the fourth slice is the largest among all slices.