The correct answer is: A. a-1, b-2, c-3, d-4, e-5
Monopoly: A market structure in which there is only one seller of a good or service. The monopolist has a great deal of market power and can therefore charge a high price and earn a high profit.
Oligopoly: A market structure in which there are a few large sellers of a good or service. The oligopolists have some market power, but they are not as powerful as a monopolist. They must therefore compete with each other to some extent.
Monopsony: A market structure in which there is only one buyer of a good or service. The monopsonist has a great deal of market power and can therefore pay a low price and earn a high profit.
Duopoly: A market structure in which there are two sellers of a good or service. The duopolists have some market power, but they are not as powerful as a monopolist or a monopsonist. They must therefore compete with each other to some extent.
Bilateral monopoly: A market structure in which there is one buyer and one seller of a good or service. The buyer and seller have equal market power and must therefore negotiate a price that is acceptable to both of them.