NO.PZ2023061903000100
问题如下：
Q. Companies most likely have a well-defined supply function when the market structure is:
选项：
A.oligopoly.
B.perfect competition.
C.monopolistic competition.
解释：
B is correct. A company in a perfectly competitive market must accept whatever price the market dictates. The marginal cost schedule of a company in a perfectly competitive market determines its supply function.
在monopolic competitive的情况下也可以嘛
