If Monopolistic Competitors Must Expect a Process of Entry and Exit

If monopolistic competitors must expect a process of entry and exit like perfectly competitive firms,

A) they will be unable to earn higher-than-normal profits in the short run.
B) they will wish to cooperate to make decisions about what price to charge.
C) they will wish to cooperate to make decisions about what quantity to produce.
D) they will be unable to earn higher-than-normal profits in the long run.