If Firms in a Monopolistically Competitive Industry Are Earning Economic

If firms in a monopolistically competitive industry are earning economic profits, then in the long run:

A) new firms producing the exact same product will enter the industry and this entry will continue until economic profits are eliminated
B) new firms producing close substitutes will enter the industry and this entry will continue until economic profits are eliminated
C) these firms can continue earning economic profits since there are barriers to entry into the industry
D) the government will most likely regulate firms in this industry to reduce these economic profits