Define comparative advantage and explain why trade occurs.

Define comparative advantage and explain why trade occurs.

• A. A country should specialize where its opportunity costs are lowest; trade allows consumption beyond production possibilities.
• B. A country should produce all goods domestically to avoid trade.
• C. Trade occurs only if countries have identical opportunity costs.
• D. Comparative advantage means zero-sum gains from trade.

Answer: (A)

Comparative advantage is the idea that each country should specialize in producing the goods for which its opportunity costs are the lowest, rather than trying to produce everything itself. When a country focuses on what it can produce relatively more efficiently (lower opportunity cost) and trades, the total world output rises. Because each country is using its resources where they perform best relative to other uses, the combined production of both goods increases, and trade lets each country consume more than it could if it produced everything domestically—its consumption possibilities expand beyond its own production possibilities frontier. So the statement that best fits is that a country should specialize where its opportunity costs are lowest and trade allows consumption beyond production possibilities. The other ideas miss the core benefit of trade: autarky ignores gains from exchanging surpluses, identical opportunity costs remove the incentive to trade, and zero-sum framing contradicts the reality that both sides can gain.

Comparative advantage is the idea that each country should specialize in producing the goods for which its opportunity costs are the lowest, rather than trying to produce everything itself. When a country focuses on what it can produce relatively more efficiently (lower opportunity cost) and trades, the total world output rises. Because each country is using its resources where they perform best relative to other uses, the combined production of both goods increases, and trade lets each country consume more than it could if it produced everything domestically—its consumption possibilities expand beyond its own production possibilities frontier.

So the statement that best fits is that a country should specialize where its opportunity costs are lowest and trade allows consumption beyond production possibilities. The other ideas miss the core benefit of trade: autarky ignores gains from exchanging surpluses, identical opportunity costs remove the incentive to trade, and zero-sum framing contradicts the reality that both sides can gain.