The Freer the Trade Between Nations

The freer the trade between nations:

A) the greater the opportunity for specialization and the greater the competition among sellers in a market.
B) the smaller the opportunity for specialization but the greater the opportunity for improved efficiency in production.
C) the greater the opportunity to use resources efficiently and the greater the opportunity for sellers to raise prices and restrict outputs.
D) the smaller the opportunity to increase the availability of goods and services and the smaller the opportunity to decrease the costs of production.