The Figure Given Below Shows the Revenue and Cost Curves

Multiple Choice

The figure given below shows the revenue and cost curves of a firm. MC represents the marginal cost curve, AC the average cost curve, MR the marginal revenue curve, and AR the average revenue curve.Figure 9.4

-A downward-sloping demand curve is faced by firms:

A) under perfect competition.
B) under perfect competition and monopoly.
C) in all market structures except monopoly.
D) in all market structures except monopolistic competition.
E) in all market structures except perfect competition.