The correect option is B
At the end of the war, widespread violence in the south led to the federal intervention of President Ulysses S. Grant in 1871, which suppressed the Klan. However, the white Democrats, who call themselves "Redeemers," regained control of the southern states one by one, sometimes using fraud and violence to control state elections. A deep national economic depression following the panic of 1873 led to important democratic advances in the north, the collapse of many railway schemes in the south and a growing sense of frustration in the north.
After this the southern economy continued to cling to its agricultural activity, taking off through it an incipient industrialization.