Suppose the production of cotton causes substantial environmental damage because the pesticides used by cotton farmers often make their way into nearby rivers and streams, and are very harmful to fish and other wildlife. Economists would consider the environmental damage that results from the production of cotton to be a(n):

A. relevant cost of production only if the environmental damage negatively affects other firms.
B. relevant cost of production only if cotton farmers are charged a fine for the damage done.
C. relevant cost of production.
D. implicit cost of production that cotton farmers will take into account when determining their profit-maximizing level of output.

Answer: C