The Amazon river is in which of these countries?

The question should specify the ‘Headwaters of the Amazon’ are in which country? When I hear about the Amazon river I think of Brazil because so much of the Amazon river is in Brazil. The only reason I got the answer right is because I reasoned out that: Amazon = South America & Peru is in South America & Peru was the only South American country in the 4 possible answers.

Smarta you are so correct..