A monopolistically competitive firm that is earning profits will, in the long run, experience all of the following except C. a decrease in the number of rival products.
Long-term economic gains or losses in monopolistic competition will be removed by entry or leave, leaving firms with no economic gains. There will be some excess capacity in a monopolistically competitive business; this could be seen as the price paid for the variety of products that this market structure brings about.
Companies engaged in monopolistic competition generate economic profits in the short term, but not over the long term. The latter is a product of the industry's open entry and departure policies as well.
To know more about monopolistic competition, refer:
https://brainly.com/question/29676613
#SPJ4