Of the following justifications for limiting trade, which one would economists be least likely to endorse? Some goods should not be imported because

a. They are important for national defense (e.g., tanks, fighter airplanes).

b. They are important for national identity(e.g., television programs).

c. Their production employs many people (e.g., cars).

d. Other countries use child labor to gain a comparative advantage (e.g., clothing).