Answer:
A. a tariff on Japanese cars, while Japan has imposed a nontariff barrier on U.S. cars.
Step-by-step explanation:
A non tarrif barrier is a restriction on a foreign product with a view of reducing its competing with local products. It is not a tax based restriction but can involve other measures such as quotas embargoes, sanctions, and levies.
Tarrifs are taxes placed on importation of foreign goods. This reduces competitiveness of the foreign goods because they will now be more expensive than locally produced goods.
In the given instance USA has imposed a tarrif on Japanese cars by taxing nearly all Japanese cars imported into the U.S.
Japan has imposed a non tarrif barrier on U.S cars by requiring that all U.S.-made cars sold in Japan be sold by existing Japanese dealers who are themselves controlled by Japanese car manufacturers.