Hello, may I have some help with this problem? The attached screenshot contains all information provided.

A firm is a natural monopoly if O A. any entrant would have the same costs. O B. it has no fixed costs. O C. its profit does not increase with output. O D. one firm can produce the total output of the market at lower cost than two or more firms could. O E. its marginal revenue is increasing faster than average costs.In a monopolistically competitive market, firms face a downward-sloping demand curve because Monopolistically competitive firms earn profits. O A. there are barriers to entry; zero economic O B. they produce a differentiated good; zero economic O C. they benefit from economies of scale; positive economic O D. they produce a differentiated good; positive economic