If the market price is $2.75 and a perfectly competitive firm is producing 1.100 units and the marginal cost to produce the 1,100 th unit is $2.75, which of the following is tre? A. The firm is not maximizing profit. B. The difference between marginal revenue and marginal cost (MR - MC) for the 500th unit is positive C. The diflerence between marginal revenue and marginal cost (MR - MC) for the 500th unit is zero. D. The difference between marginal revenue and marginal cost (MR - MC) for the 600th unit is negasve.