For a Pure Nondiscriminating Monopolist, Marginal Revenue Is Less Than

For a pure nondiscriminating monopolist, marginal revenue is less than price because

A) the monopolist's demand curve is perfectly elastic.
B) the monopolist's demand curve is perfectly inelastic.
C) when a monopolist lowers price to sell more output, the lower price applies to all units sold.
D) the monopolist's total revenue curve is linear and slopes upward to the right.