One Reason That Supply Curves Display Positive Slope Is That

Multiple Choice

One reason that supply curves display positive slope is that:

A) expanded production may require the use of superior resources.
B) people are not willing to pay a higher price for more goods.
C) expanded industry output might cause a labor shortage and subsequently increase the wage rate included in the cost of production.
D) extra production brings in the more efficient, lower-cost producers.
E) the law of diminishing returns is important to producers.