Which trade restriction was implemented to shield U.S. automobile manufacturers from foreign competitors between 1981 and 1984?
Explanation
During the period from 1981 to 1984, the Japanese government imposed export quotas on automobiles to limit the number of cars sent to the U.S., effectively protecting American auto manufacturers from foreign competition. Other measures such as export tariffs, import quotas by the U.S., or domestic subsidies were not the primary trade barriers used in this case.