Suppose that Canadian farmers can grow wheat more cheaply than can U.S. farmers. In the interest of efficiency, what is the desirable outcome?

Question

1) Allow the Canadian farmers to sell their wheat for a lower price.

2) Pass a law in Canada mandating a minimum price for wheat equal to what is charged by U.S. farmers.

3) Pass a law in the United States mandating a maximum price for wheat equal to what is charged by Canadian farmers.

4) Have U.S. citizens boycott Canadian wheat.