In Figure 23

Multiple Choice

In Figure 23.3,diagram "a" presents the cost curves that are relevant to a firm's production decision,and diagram "b" shows the market demand and supply curves for the market.Use both diagrams to answer the following question: If the market demand curve is D2 in Figure 23.3,then in the long run,

A) Economic profit is less than zero,and firms will exit.
B) Economic profit is greater than zero,and firms will expand production.
C) There are zero economic profits,so there will be no entry or exit.
D) There are zero economic profits,so firms will exit.