Answer: Neither the average cost nor the marginal cost curve.

In monopolistic competition, there is no well-defined supply function. The firm's optimal output level is determined by the intersection of marginal cost (MC) and marginal revenue (MR), while the price is set based on the market demand schedule. Unlike perfect competition, where the supply curve is represented by the marginal cost curve, neither the average cost nor the marginal cost curve serves as the supply curve in monopolistic competition. This is because the supply curve should reflect the quantity the firm is willing to supply at various prices, which is not directly represented by either cost curve in this market structure.

Author: LeetQuiz Editorial Team