Which of the Following Is True About a Perfectly Competitive

Which of the following is true about a perfectly competitive firm in the long run and in the short run?

A) The supply curve in the short run is usually steeper than the supply curve in the long run.
B) The supply curve in the short run is usually flatter than the supply curve in the long run.
C) The demand curve in the short run is usually steeper than the marginal cost curve in the long run.
D) The supply curve in the short run is usually steeper than the average total cost curve in the long run.