Refer to the Graph Shown of a Monopolistically Competitive Firm

Refer to the graph shown of a monopolistically competitive firm. In the long run:

A) marginal cost will fall for firms that remain as other firms exit the industry.
B) average total cost will rise for firms that remain as other firms enter the industry.
C) demand will fall for firms that remain as other firms enter the industry.
D) demand will rise for firms that remain as other firms exit the industry.