B. and D.
I believe, but I am not 100% sure!
To avoid policies that would draw the U.S into international conflict.
<span>The so-called Dark Ages were a giant economic Depression which lasted 300 years - and the only way you could survive was out scratching any kind of food out of the soil. But by Medieval times, things were more organized, and people could afford to live in town. There were various jobs - each person no longer had to do everything needed for survival. People could share the things they made and still live.
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