Which of the following can reduce the number of cars imported?

Question

Quizplus · Accepted Answer

A tariff is a tax on imported goods, which makes imported cars more expensive and therefore reduces the demand and the number imported. 
A quota sets a limit on the number of cars that can be imported, which directly reduces the number imported. 
A ban prohibits the importation of cars altogether, which obviously reduces the number imported to zero. Therefore, all of the aforementioned methods can reduce the number of cars imported.

Which of the Following Can Reduce the Number of Cars