What Attitudes Do Most Utilitarians Take Toward Moral Rules

What attitudes do most utilitarians take toward moral rules?

A) Many moral rules are absolute and must never be broken.
B) Moral rules can be helpful but can be broken if doing so is optimific.
C) Following moral rules is harmful and ought to be shunned.
D) Utilitarians believe that the idea of a "moral rule" is incoherent.