can someone help me this world history no one answers on the histroy section

Question

anonymous · Answer

the question is 
Which of the following rivers form international boundaries between the United States and its neighbors?



a. 

the Mississippi and the Colorado 


b. 

the Ohio and the Missouri 


c. 

the Rio Grande and the St. Lawrence 


d. 

the Illinois and the Columbia

anonymous · Answer

It seems like this question could be answered by looking at a map. I'm not aware of a river between US and Canada so I would start looking at the southern border.