A Firm Sells Grapefruit in a Perfectly Competitive Market at a Price

A firm sells grapefruit in a perfectly competitive market at a price of $1.50 per pound. The firm's marginal revenue:

A) is equal to $1.50.
B) is less than $1.50.
C) is greater than $1.50.
D) decreases from $1.50 and reaches zero as the output of the firm increases.
E) increases from zero and reaches $1.50 as the output of the firm increases.