You Are to Receive Five Gold Coins from Your Great

Multiple Choice

You are to receive five gold coins from your great uncle as an incentive to study hard.The coins were originally purchased in 1982.Your great uncle will deliver the coins the week after finals (assuming your grades are "acceptable") .The amount your great uncle paid for the coins is a(n) :

A) opportunity cost.
B) indirect cost.
C) sunk cost.
D) overhead cost.