单选题

Four countries operate within a customs union. One country proposes moving to a common market structure. What additional level of economic integration between the countries would most likelyarise if this change took place? They would:

A、 establish common trade barriers against non-members.
B、 begin to allow free movement of the factors of production.
C、 establish common economic institutions and coordination of economic policies.

【正确答案】 B

【答案解析】

B is correct. A common market structure incorporates all aspects of the customs union and extends it by allowing free movement of factors of production among members.