Which of the following statements about oligopolies is not true? O A. Oligopolies have market power in the United States, but must also deal with foreign competition. O B. Oligopolies can charge prices higher than their marginal cost. O C. Oligopolies can be easily broken up and turned into perfectly competitive firms. D. Oligopolies can produce both differentiated and homogeneous products. O E. Since oligopolies have economies of scale, they can generate lower prices for their consumers