Did the vast majority of native Americans reside in north america

No, before the European conquests a larger number of native Americans were in South america.

Explanation:

South America housed some of the biggest civilizations of the Native American culture throughout the history and there were many fertile regions there with deep rooted histories of ethnic groups.

Although in the later period great civilizations like Aztecs and Inca did develop in Northern America and the population there was considerably high too, especially in the Mexico region.

South America still had more people than North America.

the real answer is b

north atlantic treaty organization.