Essentials of Economics 7th Edition by Gregory Mankiw

Exercise 21

If a nation that does not allow international trade in steel has a domestic price of steel lower than the world price, then
A) the nation has a comparative advantage in producing steel and would become a steel exporter if it opened up trade.
B) the nation has a comparative advantage in producing steel and would become a steel importer if it opened up trade.
C) the nation does not have a comparative advantage in producing steel and would become a steel exporter if it opened up trade.
D) the nation does not have a comparative advantage in producing steel and would become a steel importer if it opened up trade.