The following table shows a profit-maximizing producer's marginal costs. The firm is operating in a perfectly competitive market and has fixed costs of $500. Quantity Marginal Cost ($) 200 2 150 3 100 A 170 230 300 420 CO 600 Refer to the above information to answer this question. What is the shut-down price? Select one: O A. $200 O B. $500. O C. $170. O D. $270. O E. $150