I want to test the ability of students to read a passage and answer questions about it. Could you please come up with a good question for the passage "As the number and size of agricultural societies increased, they expanded into lands traditionally used by hunter-gatherers. This process of agriculture-driven expansion led to the development of the first forms of government in agricultural centers, such as the Fertile Crescent, Ancient India, Ancient China, Olmec, Sub-Saharan Africa and Norte Chico."? 

What are associations of farms called?