One Difference Between Perfectly Competitive Markets and a Single-Price Monopoly

Multiple Choice

One difference between perfectly competitive markets and a single-price monopoly is that

A) marginal revenue equals marginal cost for perfectly competitive firms, but not for single-price monopolists.
B) marginal cost equals average variable cost for perfectly competitive firms but not for single-price monopolists.
C) price equals minimum average total cost for single-price monopolists but not for perfectly competitive firms.
D) marginal revenue equals price for perfectly competitive firms, but not for single-price monopolists.
E) none of the above