Answer:
Letter b is correct. A monopolistically competitive firm faces competition from firms producing close substitutes.
Explanation:
Monopolistic competition is an economic situation that occurs when companies exhibit imperfect competition, that is, companies market similar but not identical products, which characterize them as substitute but not perfect substitute products.
Products may have different variables, such as quality, price and reputation in the market. The greater the degree of product differentiation, the more price control the company will have.