A Single-Price Pure Monopoly Is Economically Inefficient

A single-price pure monopoly is economically inefficient

A) only because it produces beyond the point of minimum average total cost.
B) only because it produces short of the point of minimum average total cost.
C) because it produces short of minimum average total cost and price is greater than marginal cost.
D) because it produces beyond minimum average total cost and marginal cost is greater than price.