PLEASE HELP

Which of the following describes how trade between the countries of North America is affected by their geographic location?


Select one:

a. High taxes make it expensive for these countries to trade with each other.


b. It costs much less to transport goods because the countries border each other.


c. Moving products is difficult since few rivers flow from the U.S. to other countries.


d. Trade is not desired since they are close together and have the same natural resources.