Garments Are Exported from China to the United States on a Daily

Garments are exported from China to the United States on a daily basis. In turn, the United States exports agricultural products like soybeans to China. Which statement best explains the trade equation between China and the United States?

A) Tariff barriers determine the flow of goods and services between nations.
B) Countries are simultaneously encouraging exports and discouraging imports.
C) First entrants to the industry ensure their nations have the first-mover advantages.
D) Nations with an absolute advantage in producing certain goods trade them for goods produced by other countries.
E) Gold and silver are the mainstays of national wealth and essential to vigorous commerce.