Will, Bill, and Phil Decide to Study an Extra Hour

Multiple Choice

Will, Bill, and Phil decide to study an extra hour for an exam. Instead of studying, they could have gone out to eat, played football, or watched TV. Which of the following statements is correct?

A) Going out to eat, playing football, and watching TV are all called sunk costs.
B) The students made a rational choice as long as they face no scarcity.
C) The marginal cost of the decision is the same if they make the same score on the exam.
D) The benefit the three students receive must be the same because they all make the same choice.
E) The students could each have different opportunity costs.