Why might recent events have led to many African Americans working for ranchers?

A: during the Civil War, many African Americans went west to work on the railroads.
B: in the 1850s, many free African Americans from the north became ranchers.
C: after the end of slavery, African-Americans could move and find new work.
D: During Reconstruction, African American politicians promoted ranching.

C: after the end of slavery, African-Americans could move and find new work.