"Which of the following statements is (are) TRUE? I. Free entry to a perfectly competitive industry results in the industry's firms earning zero economic profit in the long run, except for the most efficient producers, who may earn economic rent. II. In a perfectly competitive market, long-run equilibrium is characterized by LMC < P < LATC. III. If a competitive industry is in long-run equilibrium, a decrease in demand causes firms to earn negative profit because the market price will fall below average total cost."A) I. II. and III B) II, III. and IV C) I and III D) I only