When Regulating a Natural Monopoly,government Officials Face a Dilemma That

When regulating a natural monopoly,government officials face a dilemma that:

A) the efficient price may not allow the firm to break even.
B) the efficient price may lead to an inefficiently high level of output.
C) the efficient price leads to an output level that is too low.
D) the efficient price may not allow the firm to enjoy positive profits.
E) long-run average costs are constantly increasing.