Final answer:
According to the theory of comparative advantage, a nation should produce goods that it is more efficient at producing than other nations.
Step-by-step explanation:
According to the theory of comparative advantage, the true statement is option 1) A nation should produce those goods which it is more efficient at producing than are other nations. Comparative advantage is the ability of a country to produce a good at a lower opportunity cost than another country. This means that even if a country is less efficient in producing all goods compared to other nations, it can still benefit from trade by specializing in the goods it can produce relatively more efficiently.