The answer is C) The rising tensions between the races.
Despite the ratification of the Thirteenth, Fourteenth and Fifteenth Amendments during the Reconstruction Era, which abolished slavery, protected the citizenship rights of black people and prohibited discrimination, the social conflict of the race wasn't entirely solved.
In reality, tensions rose between freed slaves and their former slaveholder. Former slaveholders now had the duty to negotiate about wages with who were their slaves before. Suddenly, emancipated slaves were protected by law and had rights they didn't have before, but American society still had a long way to run before race equality became the norm.
