The Tragedy of the Commons will be evident when a growing number of sheep grazing on the town commons leads to the destruction of the grazing resource. To correct this problem, the town could _____.
a. allow individual shepherds to choose their own flock sizes.
b. internalize the externality by subsidizing the production of sheep's wool.
c. auction off a limited number of sheep-grazing permits.
d. wait until the market corrects the problem.