Which of the following is the best example of negative marginal utility?

A. Your first Snickers bar in weeks tastes like perfection and you savor every bite.
B. Your fifth serving of pie tastes stale so you don't enjoy it as much as the first serving of pie.
C. Your fourth motorcycle sits in the garage never having been used.
D. Your third TV is still in the box and you regret that you were talked into buying it.