Answer: 1. Fertile soil for crops
Step-by-step explanation:
The civilizations that grew in Mesopotamia were some of the earliest known to have engaged in Agriculture. They did this due to the fertile soil that the flooding of the Euphrates and the Tigris deposited on the floodplains.
These fertile soils allowed for crops to grow quickly and in abundance and with the rivers there to water the crops, farming quickly took hold in the early civilizations of Mesopotamia leading to the emergence of city states like Ur.