C. They had nowhere to go
Many slaves wanted to run away but they had nowhere to go.
A. Militarism. is the answer.
I think it's all of them except the first one, Germany was not occupied by the allies :)
http://www.bbc.co.uk/schools/gcsebitesize/history/mwh/ir1/thetreatyrev1.shtml
<span>Minamoto Yoshitsune, led his clan to victory against the Taira near the village of Dan-no-ura.
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It would be a "traditional" type of economic system that relies primarily on hunting gathering herding and farming to maintain self sufficiency, since this was how humans sustained life for many years before the modern era.