The basis for international trade is that:
a. a nation can import a particular good at a lower cost than if it were produced domestically.
b. we stand to gain if we can sell more to other nations than they buy fro us
c. there are winners and losers
d. it pays to trade, provided we remain independent by producing all our necessities.
I put a is that right.
Yes, you are correct. The basis for international trade is that a nation can import a particular good at a lower cost than if it were produced domestically. This concept is known as comparative advantage. Comparative advantage means that even if one country can produce all goods more efficiently than another country, both countries can still benefit from trade if each specializes in producing the goods in which they have a comparative advantage.
To determine which country has a comparative advantage, economists compare the opportunity costs of producing a good. The opportunity cost is the value of the next best alternative that must be forgone in order to produce a particular good. If a country can produce a good with a lower opportunity cost, it has a comparative advantage in producing that good and should specialize in its production.
So, in summary, option (a) correctly states the basis for international trade.