Which of the Following Statements Is Not Correct

Multiple Choice

Which of the following statements is not correct?

A) In a long-run equilibrium, marginal firms make zero economic profit.
B) To maximize profit, firms should produce at a level of output where price equals average variable cost.
C) The amount of gold in the world is limited. Therefore, the gold jewelry market probably has a long-run supply curve that is upward sloping.
D) Long-run supply curves are typically more elastic than short-run supply curves.