Respuesta :
The correct answer in this case is that A - They all had agricultural economies.
The reason why this is so is because having a big civilization brings a demand for a lot of food with it. This is something all of the civilizations shared between each other. All of them were big and required a lot of food to be able to sustain themselves - and supplying a civilization with big amounts of food was most easily done by agriculture.
The reason why this is so is because having a big civilization brings a demand for a lot of food with it. This is something all of the civilizations shared between each other. All of them were big and required a lot of food to be able to sustain themselves - and supplying a civilization with big amounts of food was most easily done by agriculture.