What does archaeology believe allowed people to build complicated society 1Surplus of food
2The building permanent structures
3A hierarchies of people
4 creation of art in artisans

1. Surplus of food

Explanation:

In order to build a a society, the very first thing that human civilization need to do is find a way to settle in an exact same place for a long period of time.  This could only happen if we have a surplus of food in that area.

Without it, we need to be a nomadic group. This require us to move from one place to another while seeking new source of foods. In such situation, we wouldn't have enough time to slowly develop our traditional tribes into a modern society.