Answer: D. Transition from hunting and gathering to settled agriculture
Step-by-step explanation: The Neolithic Revolution was the critical transition that resulted in the birth of agriculture, taking homo sapiens from scattered groups of hunter-gatherers to farming villages and from there to technologically sophisticated societies with great temples and towers and kings and priests who directed the labor other subjects and recorded their feats in written form.
The Neolithic Revolution was viewed as a single event-a sudden flash of genius- that occurred in a single location, Mesopotamia, between the Tigris and Euphrates Rivers in what is now southern Iraq, specifically the site of a realm known as Sumer, which dates back to about 4000 B.C.E It then spread to India, Europe, and beyond. Most archaeologists believed this sudden blossoming of civilization was driven largely by environmental changes. The gradual warming as the Ice Age ended that allowed some people to begin cultivating plants and herding animals in abundance.