Which of the Following Factors Does Not Help Explain Incomplete

Multiple Choice

Which of the following factors does not help explain incomplete specialization by countries that trade in accordance with comparative advantage?

A) There may be high transportation costs for perishable products or human services.
B) The economies of trading partners may be of vastly different sizes.
C) Opportunity costs of production may not be constant,but may vary with the volume of production.
D) Governments may impose all kinds of barriers to free international trade,such as tariffs and quotas.
E) The cost of making trade deals may have become extremely low because of the existence of the World Trade Organization.