What was the main reason Allied troops were horrified when they discovered Nazi concentration camps?

They had not expected to find thousands of dead or dying prisoners

Explanation:

One of the main things that made concentration camps so horrific was the way the prisoners were treated. They were malnourished, over-worked (sometimes to the point of death), tortured, raped, and put to death in gruesome and inhumane ways.

- "made the south's economy grow rapidly and a small effect that a lot of people don't know is that it made the more demand of slaves and cotton products. and also new states formed due to plantations growing in size."

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