Measured as a share of the economy, the size of the trade sector (exports plus imports) of the United States has

A) been increasing since 1980, but it declined during 1960-1980.
B) been relatively constant during the last four decades.
C) increased by about 10 percent during the last four decades.
D) approximately doubled since 1980 and tripled since 1960.

Trade Sector

Refers to the part of a country's economic activity that is involved in the exchange of goods and services, domestically and internationally.

Economy

The system of production, distribution, and consumption of goods and services in a particular geographical region.

Exports

Goods or services that are produced in one country and sold to customers in other countries.