Fill in the blank to complete the sentence. Be sure to check your spelling carefully. The first civilization was that of the

Civilizations first appeared in Mesopotamia (what is now Iraq) and later in Egypt. Civilizations thrived in the Indus Valley by about 2500 BCE, in China by about 1500 BCE and in Central America (what is now Mexico) by about 1200 BCE. Civilizations ultimately developed on every continent except Antarctica.

Explanation:

I hope this helps!

answer: (fluidity)is the correct answer.

explanation: because of this characteristic, success on the battlefield depends in large part on the ability to adapt to proactively change events to our advantage as well as to react quickly to constantly changing conditions