-The Above Figure Shows the Market Demand Curve for Long-Distance

-The above figure shows the market demand curve for long-distance land-based telephone calls. Suppose the marginal cost of a long-distance telephone call is 2 cents per minute for a call no matter how many minutes of calls are made and there are three firms in the industry. If the firms in the industry operate as perfect competitors, there are ________ minutes of calls made per hour.

A) between 0 and 3 million
B) more than 5 million and less than or equal to 7 million
C) more than 3 million and less than or equal to 5 million
D) more than 9 million
E) more than 7 million and less than or equal to 9 million