A competitive firm produces a product using labor and plastic. The firm is initially in equilibrium. If the cost of plastic suddenly increases, which of the following will occur?
A. The demand curve for the product will shift to the left.
B. The firm's demand curve for plastic will shift to the left.
C. The firm will increase the number of units offered for sale.
D. The firm will definitely go out of business, since competitive firms earn zero economic profits in equilibrium.
E. The firm's marginal costs will increase at each level of output.
