A firm can earn economic profits in the short run A. only when the market is monopolistically competitive or perfectly competitive. B. when the market is perfectly competitive, monopolistically competitive, or monopolistic. C. only when the market is perfectly competitive. D. only when the market is a monopoly or monopolistically competitive.

A firm can earn economic profits in the short run (D)only when the market is a monopoly or monopolistically competitive.

Explanation:

In the short run, a monopolistic competitor can maximize profit by selecting the minimum efficient scale

When price is equal to average cost, economic profits tend to be  zero. Thus, although a monopolistically competitive firm may earn positive economic profits in the short term.

If the firms in a monopolistically competitive market are earning short-run economic profits, then each firm's profit will drop to normal in the long run as its demand curve shifts leftward due to entry of new firms

Monopoly: the term monopoly refers to a market where one company is the sole supplier.

Monopolistic competition: It  REFERS to a type of imperfect competition where in one or two producers sell products that are differentiated from one another as goods but are  not perfect substitutes for each other

answer; is the sum of all individual demands curves;