Option (d), There are only two companies working in the same industry as one in the United States. This sector of the economy is probably an oligopoly.
A small number of companies compete in an oligopoly market and are aware of how their pricing and production strategies are interdependent. Because there are only a few number of businesses, each one has a respectable level of market power.
Oligopoly occurs when a small number of large enterprises account for all or almost all of an industry's sales. The auto industry, cable television, and commercial aviation are just a few examples of the several industries that display oligopoly.
Oligopolies can be identified using concentration ratios, which determine the proportion of the market that one firm controls. When an industry has a high concentration ratio, economists usually define it as an oligopoly.
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