(A) a growth in racial tensions between blacks and whites
(B) went back to being treated unfairly
(C) lost many of their jobs
(D) ** experienced a growth in job opportunity
EXPLANATIONS BELOW
Concept note-1: -Following the Civil War, the railroad was the most important industry that African Americans worked in. In the South, freed slaves had few fates to choose from, among them sharecropping, domestic service, and railroading.
Concept note-2: -Four million newly freed African Americans faced the future of previously-unknown freedom from the old plantation system, with few rights or protections, and surrounded by a war-weary and intensely resistant white population.