A Patent That Confers the Monopoly Right to Produce an Essential

A patent that confers the monopoly right to produce an essential prescription drug tends to increase the incentive the develop new and better prescription drugs while

A) imposing no cost upon society as a whole.
B) lowering the cost of prescription drugs to the public.
C) eliminating the monopolist's costs of defending its rights to the patent.
D) creating a "deadweight loss" of monopoly-induced inefficiency.