Answer:
D. Bloody attacks in which entire populations of cities and towns were often wiped out.
Step-by-step explanation:
Genghis Khan was the founder and first Great Khan of the Mongol Empire which became the largest contiguous empire in history after his death.
He was known for the brutality of his campaigns and is considered to be a genocidal ruler. The Mongol Empire developed during the 13th century through a series of victorious campaigns throughout Asia. During that time the Empire hundreds of cities and villages and killed millions of men, women, and children.
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