What two countries border the most populous nation in the western hemisphere?

Two of the most populated countries of the Western Hemisphere are Canada with 36.28 million population and along with this country is Mexico with 127.5 million. Mexico is the country that lies between the United States, Guatemala and Belize. On the other hand, Canada is the North American country that stretches from the US in the South to the Arctic Circle in the North.

Ithink it’s letter a if i’m not wrong .