To correct for positive externalities, the government should:_________
(A) do nothing, since no harm is done by positive externalities
(B) levy a tax on the output of the good or service
(C) pay a subsidy equal to the marginal external benefit
(D) impose a price ceiling on the good to discourage its production
(E) impose a price floor on the good at which the marginal private benefit equals the marginal social cost