Which of the Following People Does an Economist Consider Underemployed

Which of the following people does an economist consider underemployed?

A) Someone who prefers to spend more time on leisure and less time on wage-earning activities
B) A person who is working fewer hours at wage-earning activities than she or he desires
C) A rock star who voluntarily chooses to work part-time
D) Someone who is in prison and is willing to work from his cell
E) A gardener who hates plants but still does the job because he or she has no other skills