four million enslaved people in the U.S. in 1860, nine out of ten lived on farms and plantations (mostly cotton plantations), and half lived in the Deep South.
I think it was because dynastic rulers were so caught up with war that they had to let china have a time of peace so they could focus on wining their wars. I hope i helped you out!
C and E are definite answers and A and B are definitely not. I suspect D isn't either but in one phase of the Korean war UN troops which were largely American pushed the North Koreans back across their own border. However I would stick with C and E.