Figure 13-9 the Figure Below Depicts Average Total Cost Functions for a for a Firm

Multiple Choice

Figure 13-9
The figure below depicts average total cost functions for a firm that produces automobiles.
-Refer to Figure 13-9. The firm experiences constant returns to scale at which output levels?

A) output levels less than M
B) output levels between M and N
C) output levels greater than N
D) All of the above are correct as long as the firm is operating in the long run.