Carol Owns a Running Shoe Store That Operates in a Perfectly

Carol owns a running shoe store that operates in a perfectly competitive market.If running shoes sell for $120 per pair and the average total cost per pair of shoes is $125 at the profit-maximizing output level,then in the long run

A) more firms will enter the market.
B) some firms will exit from the market.
C) the equilibrium price per pair of shoes will fall.
D) average total costs will fall.