The seas allowed for trade with other civilizations.
Water was needed for raising animals.
Explanation:
All mentioned option except Water provided power for electricity are correct because of the simple reason that the electricity didn't existed in the 4th millennium BC when this first settlements were created. This settlements were created in the area between Egypt and Mesopotamia in the shape of crescent, thus we have that name. Of course, they needed water to crop, as agriculture was widespread, but the seas also allowed them trade, especially between Egypt and Mesopotamia.
