Congress reacted to Klan terror by passing a. Radical Reconstruction. b. the Enforcement Act of 1870. c. the Compromise of 1877. d. the Thirteenth Amendment.

The correct answer is B. The Enforcement Act of 1870.

Indeed, President Grant had taken power after Lincoln's assassinations and was committed to make sure Southern states would abide by federal laws concerning the civic rights of black Americans.

The Ku Klux Klan was terrorizing freedmen and women and preventing them from exercising the right to vote, to be elected as a public servant or official and even to seek protection from the police and demand judicial redress from courts. Most members of the Klan were arrested, prosecuted and jailed and the Klan was virtually annihilated.