Consider a perfectly competitive market in which all firms have the same costs. Choose the statement that is incorrect.
A. The market supply curve is upward sloping at prices above the​ firm's shutdown price.
B. Each firm takes the market price as given and produces its​ profit-maximizing output.
C. In the short​ run, a firm cannot incur an economic loss.
D. Market demand and market supply determine the market price and market output.