The correct answers are A) as the fields of Sumer grew saltier, harvests were less plentiful and B) Wars among the city-states plagued the Sumerians.
The statements that were a factor in the decline of Sumer were "as the fields of Sumer grew saltier, harvests were less plentiful and wars among the city-states plagued the Sumerians."
Sumer was the oldest civilization known to humans. Historians consider that Sumerian people established 5,500 years ago in the middle of the Tigris and Euphrates Rivers in the Middle East, in what today is the region of Bagdagh, Iraq. Also known as Mesopotamia, this ancient civilization flourished with great city-states such as Ur, Lagash, Uruk, and Kish. However, Sumer started to decline when the fields of Sumer grew saltier, harvests were less plentiful and wars among the city-states plagued the Sumerians.
