Under Which of the Following Situations Will a Tariff Imposed

Under which of the following situations will a tariff imposed by a country fail to reduce imports by as much as expected?

A) The current tariff rate is less than the prohibitive tariff rate.
B) The foreign export quantity supplied of the good imported by this country is more responsive to changes in the world price than was expected.
C) The domestic supply of the import-competing products is more price-elastic than was expected.
D) The domestic quantity demanded of the imported product is less responsive to price changes than was expected.