The correct answer is d. hunting -gathering.
Hunting and gathering was already existing before this : in fact the neolithic revolution was going away from this lifestyle and starting farming and domestication of animals.
I believe the answer is C. Hope this helps
The ancestors of living Native Americans arrived in what is now the United States at least 15,000 years ago, possibly much earlier, from Asia via Beringia. A vast variety of peoples, societies and cultures subsequently developed.
Slash and burn agriculture would have been practiced most prominently in the river valleys of Egypt, since this is were lots of plant life existed, which needed to be eliminated to make room for fields.
