Suppose that a firm produces more than the optimal quantity (that is, more than the profit-maximizing output). What is a possible reason for this error? Select one: O a. The firm is a natural monopoly. O b. The firm is a first-degree price discriminating monopolist. O c. The manager ignores some implicit marginal costs of production so that the perceived MC curve is below the actual MC curve. O d. The manager miscalculated the marginal costs of production so that the miscalculated MC curve is above the actual MC curve. O e. None of the above