Answer:
Mesopotamia is situated in between the Tigris and Euphrates river, and is thus suitable for civilization.
Step-by-step explanation:
Most, if not all early civilizations started near a river or body of fresh water. Reason being, these bodies of water contained the necessary requirements for human life to thrive. It gave people water, food, and was even useful for farming, as the floods would bring about fertile soil once the waters receeded.
A little tidbit:
This is also why Mesopotamia is directly translated as "Between two rivers".