What Is the Major Drawback of Command and Control as a Means

What is the major drawback of command and control as a means of pollution control policy?

A) Producers have no incentive to reduce pollution past the set standard.
B) CAC is very expensive to implement
C) Most producers refuse to implement CAC
D) Latin American governments do not have the authority to enforce CAC
E) CAC does not lead to the socially optimal level of output for pollution intensive goods