According to economists, one reason few professional athletes have PhD’s is that the a. opportunity cost of going to graduate school is too high. b. marginal benefit of going to graduate school is too high. c. explicit cost of going to graduate school would be too high.

OPPORTUNITY COST OF GOING TO GRADUATE SCHOOL IS TOO HIGH. Option A.

Explanation:

Opportunity cost is a key concept in economics, and has been described as expressing "the basic relationship between scarcity and choice". Opportunity costs are not restricted to monetary or financial costs: the real cost of output forgone, lost time, pleasure or any other benefit that provides utility should also be considered an opportunity cost.

the autor of the text is bringing the point that one achievment of the president john f. kennedy was a success and this caused the next president to use a similar idea. the purposefor the use of the quotation in the text is to support the idea that peace corps was a result of the president's call. in this case, the quotation is presented as part of the writing and does not stand on its own.

answer a.