Final answer:
The key determinant for a country to gain from international trade is comparative advantage, which allows for specialization and drives gains from trade even if a country has an absolute advantage in all goods.
Step-by-step explanation:
Absolute vs. Comparative Advantage in International Trade
The key determinant in whether a country can gain from specialization in international trade is comparative advantage. Despite a country having an absolute advantage in producing all goods, it can still benefit from international trade by focusing on the goods that it can produce at a relatively lower cost compared to other goods. Absolute advantage means that a country can produce a good using fewer resources compared to other countries; however, comparative advantage dictates that a country should produce and trade goods that it can create at a lower opportunity cost than others. This lower opportunity cost means giving up less of other goods to produce it.
By specializing in the production of goods where a country has a comparative advantage, each country can gain through trade. This specialization encourages efficiency and increases the total output for trading countries, creating gains from trade.