The Answer is A. Democracy
Well, the Sumerians were very hard working and inventive people; most of their inventions are actually used today by almost everyone! (If you didn’t already know) Sumerians invented the first written language, cuneiform, the wheel, the sail boat, the game “Checkers” and much more.
By Sumerians working together they not only created those things, but they also started trading with others which fulfilled them with much needed food, clothing, and raw materials. So by them opening up to trade, they were able to prosper longer.
I hope this helps what you are looking for!
Austin-
