The government placed _____ on the numbers of foreign cars that could be imported.
A.limitations
B.restraint
C.requirements
D.restrictions
D
restriction(可数名称)限制性规定:It is a club with rigid restrictions on its membership.Limitation局限性,不足之处,不利之处(可数):1)I know my limitations.(我了解我的不足之处。) 2)Every from of art has its limitations.(每种艺术形式都有其局限性。)