Final answer:
Adam Smith recommended free trade to promote economic competition, encourage specialization and efficiency, and benefit individuals and countries.
Step-by-step explanation:
Adam Smith recommended free trade, that is, international trade with no tariffs or other governmental barriers to trade, in order to promote economic competition, encourage specialization and efficiency, and benefit individuals and countries. Smith believed that by allowing countries to trade freely without government interference, each country could focus on producing goods and services that it is most efficient at, leading to increased productivity and economic growth.