Consider the Short- Run and Long- Run Cost Curves for a Firm.If

Consider the short- run and long- run cost curves for a firm.If factor prices decrease,

A) there will be no change in the cost curves in the long run.
B) the firm will move down along both its long- run and short- run average cost curves.
C) both the long- run and short- run average cost curves will shift downward.
D) the firm will move down along its long- run average cost curve only.
E) there will be a downward shift in the long- run average cost curve but not in the short- run average cost curve.