Question

Please help I know this is not history related but I need help on this one question I need a direct answer but I will guess

Free trade among countries can be restricted by all of the following except

Answer 1

What are your options?

Answer 2

import taxes.
trade barriers.
import quotas.
increased use of raw materials.

Answer 3

sorry about that :)

Answer 4

Increased use of raw materials would not restrict trade.

Answer 5

Ok thanks you so much

Answer 6

It's simply a supply and demand matter not a regulation.

Answer 7

@sgstiles is correct

Answer 8

That is what I thought it was after reading WiKi