A Monopolistically Competitive Firm Is Currently Producing 25 Units of Output

A monopolistically competitive firm is currently producing 25 units of output. At this level of output the firm is charging the highest price it can at $30, has marginal revenue equal to $21, has marginal cost equal to $21, and has average total cost equal to $22. From this information we can infer that

A) the firm is currently maximizing its profit.
B) the firm is earning zero profit.
C) increasing the quantity produced will raise per-unit costs.
D) firms are likely to leave this market in the long run.