An Efficient Amount of a Public Good Is Unlikely to Be

An efficient amount of a public good is unlikely to be produced in a free market because

A) of the high cost of producing the public good.
B) of the existence of adverse selection.
C) there is no way to prevent a person who is not willing to pay for the good from receiving benefits from the good.
D) of the existence of moral hazard.
E) social benefits exceed social costs.