I’ve yet to see a Mongolian Norwegian.
We are Eurasian. Mongolians, Europeans, and Indians all have more in common with each other than any does with an African or a Thai/Pacific Islander.
So if we are going with just three (ignoring our Australians again, why must you always ignore the Australians and New Guineans?) it would be ....
1)Africans
2)Eurasian Mongoloids(including American Indians), and
3)Pacific Islanders.
So what (again) is the mechanism that we would derive your these three races that you insist upon?