What was the longest lasting victory for civil rights achieved during Reconstruction?

OA. passage of Black Codes and Jim Crow laws in the South
O B. establishment of a strong two-party political system in the South
O C. ratification of the Thirteenth, Fourteenth, and Fifteenth Amendments
O D. increased prominence given to the office of the president of the United States

C. ratification of the Thirteenth, Fourteenth, and Fifteenth Amendments