Answer:
well they were called the river civilization do to the fact that there were rivers that gave them fresh water. they were also called the river civilizations because rivers help to create good farmland so because there were by the water they had better crops and back then the better the crop the more you would get when you trade so they were called the river civilization do to the fact that they used the revisers near by as there way of life
Step-by-step explanation:
sorry if im late and tell me if im wrong also i did not know if you needed more then one paragraph so i did one