Trade enhances the economic well-being of a nation in the sense that:

a. trade puts downward pressure on the prices of all goods.
b. both domestic producers and domestic consumers of a good become better off with trade, regardless of whether the nation imports or exports the good in question.
c. the gains of domestic producers of a good exceed the losses of domestic consumers of a good, regardless of whether the nation imports or exports the good in question.
d. trade results in an increase in total surplus compared with a closed economy.