Countries A and B both produce coffee. Both countries belong to GATT. Country A imports coffee from B. Once B's coffee enters A's stream of commerce, under the national treatment provisions of GATT:

a.

country A cannot subject B's coffee to higher internal taxes or charges than its domestic coffee.

b.

country A may now charge higher internal taxes or charges on B's coffee in order to discourage coffee drinking since the goods have already passed the border.

c.

country A cannot subject B's coffee to any internal taxes or charges, even if it does so to domestic coffee.

d.

none of these are correct.