How Will Unit (Average) Cost of Manufacturing (Materials, Labor and Overhead)

Multiple Choice

How will unit (average) cost of manufacturing (materials, labor and overhead) usually change if the production level rises?

A) It will remain constant.
B) It will increase in direct proportion to the production increase.
C) It will increase, but inversely with the production increase.
D) It will decrease inversely and in direct proportion to the production increases.
E) It will decrease, but not in direct proportion to the production increase.