Define "comparative advantage."

Comparative advantage refers to the ability of an individual, firm, or country to carry out a particular economic activity at a lower opportunity cost than another entity. This concept highlights that even if one country is less efficient in producing all goods compared to another country, it can still benefit from specialization and trade by focusing on the goods it produces relatively more efficiently.

For instance, if Country A can produce both cars and textiles but has a much lower opportunity cost for textiles, while Country B has a lower opportunity cost for cars, both countries can benefit from specializing in what they produce best and trading with each other. This mutual specialization allows countries to enjoy a greater total output and variety of goods.

The other provided options do not align with the definition of comparative advantage; they focus on absolute efficiency or trade logistics rather than the core principle of opportunity cost, which is essential to understanding why comparative advantage is such a crucial element in international trade and economics.