A. They are mostly the product of the complex financial systems that only developed at the end of the Middle Ages.
B. They are very profitable for owners, but usually result in dissatisfied producers and consumers.
C. The Portuguese were the only European power to avoid monopolies, finding them morally objectionable.
D. Monopolies provide consumers with the lowest price possible, since a company with a monopoly does not have to worry about competition.
Answer: B.