Who Among the Following Is a Free Rider

Multiple Choice

Who among the following is a free rider?

A) Barry buys candy from the store where he works.
B) Betty rides to work with Sally,but she pays Sally for gasoline and other travel-related expenses.
C) Joe drives 20,000 miles a year on public streets,but he pays no more in property taxes than Sam,who only drives 1,000 miles.
D) Fred watches many public television programs,but he has never sent in a contribution to the station.