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

Multiple Choice

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

A) marginal revenue equals marginal cost for perfectly competitive firms, but not for monopolists.
B) marginal revenue equals price for perfectly competitive firms, but not for single-price monopolists.
C) marginal cost equals average variable cost for perfectly competitive firms but not for monopolists.
D) All the above answers are correct.