-The U-Shaped Average Total Cost Curve Is

Multiple Choice

-The U-shaped average total cost curve is

A) a result of constant marginal returns.
B) a result of firms' wanting to find the output level where cost is at its minimum.
C) a result of increasing marginal returns.
D) unrealistic because average total cost always increases as output increases.
E) the result of average fixed cost falling and decreasing marginal returns as output increases.