CLEP Microeconomics Exam Prep

Answer - D - All of the above might be reasons that a monopoly could exist.

Key Takeaway: There are four kinds of market structures: perfect competition, monopoly, oligopoly, and monopolistic competition. Monopolies have few products, severely restrict entry of companies and firms, and products tend to be unique. In contrast, perfect competition markets have many products and make it easy for companies and firms to present their products. A monopoly might exist because economies of scale exist; because a business owns a patent on a good, service, or idea; or because one business owns all of the important resources used to make their products.