Why did it take so long for the north and south to really be united again?

(a)some wanted to punish the south.
(b)they were hoping to never be united.
(c)they were trying too hard.

Hey!me its for an important test! ! which issue during the progressive era would most likely have united mary harris "mother” jones and lewis hine? a) ending child labor b) regulating monopolies c) using photography to expose poor working conditions d) exposing the lack of jobs available for untrained laborers