A monopoly is producing a level of output such that marginal revenue is equal to marginal cost. The firm is selling its output at a price of $10 per unit and is incurring average variable costs of $5 per unit and average total costs of $8 per unit. Given this information, it may be concluded that the firm:

A. is operating at maximum total profit

B. is operating at a loss that could be reduced by shutting down

C. is operating at a profit that could be increased by producing more output

D. is operating at a loss that is less than the loss incurred by shutting down