Monopoly marginal cost regulation

From the explanation of the mock question:

“Monopolists forced to operate where price equals marginal cost will suffer losses and go out of business rather than face such regulation.”

Since for monopoly, usually MC > ATC I cannot agree with above quote?

As I can price MC which is greater than ATC I have a gain?

u mess up concepts again, aco :smiley:

here is graph depict natural monoply