During times of high unemployment, colleges often observe an increase in enrollment even if tuition remains unchanged. Why?

A.The benefit of attending college is lower because college graduates are less likely to find jobs.

B.The opportunity cost of attending college is higher when unemployment is high.

C.The opportunity cost of attending college is lower when unemployment is high.

D.Students go to college even when the net benefit is negative.

正确答案：The opportunity cost of attending college is lower when unemployment is high.