What climate conditions led to the formation of the world’s earliest known civilization?

Wet and tropical climate conditions led to the formation of the world's earliest known civilization.

Explanation:

The Mesopotamian Civilization that began more than 5100 years ago was initially limited to the area that lies between River Tigris and River Euphrates. The river flowed from the eastern highlands of turkey through Iraq and Syria. Every year, that region was flooded which was destructive though it increased the soil quality.

The wet and tropical climate in this region made the region suitable for carrying out most human activities. Thus, most people chose this and the surrounding region for their settlement and the region soon turned into a huge civilization.

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