How do european nations compare to the u. s. in terms of number of slaves and timelines for banishment of slavery?

While there was slavery in the past in European nations as well, it wasn't as rampant as it was in the United States where there were a lot of plantation owners who also owned multiple slaves and whole families at times - before this was made illegal during the US civil war. 

Ithink the answer is b : )

C. congress was able to pay debts run up in the war