An import quota

a. is a supply restriction limiting the quantity of a good that can be imported.

b. is a price floor imposed on an imported good.

c. is a price ceiling imposed on an imported good.

d. is a legislative requirement stating that firms which import some of their merchandise must hire a certain number of immigrant workers.

The correct answer is letter "A": is a supply restriction limiting the quantity of a good that can be imported.

Explanation:

A quota for imports applies to set limits on the number of goods that can be imported into a country over time. Countries are using quotas to shield domestic companies. This limits the supply of those goods by imposing a top on foreign goods being imported, which keeps prices high so that domestic companies can still sell their goods at a fair price.