Answer :
Neo-Assyrians civilization developed a violent method of conquest known as "calculated frightfulness".
Neo-Assyrians
Neo-Assyrian was an Ancient civilization located in Mesopotamia.
The civilization was known for military strategies and strength.
They had a standing army, trained in siege warfare, war tactics, and fighting (hand-to-hand).
They used chariots, horses, iron weapons, lances, etc.
The Neo-Assyrians, with their military campaign, were able to create the largest empire in the world.
Thus option D. is the correct answer.
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