By what methods did southern whites seek to limit african-american civil rights and liberties? how did the federal government respond?

Through the Black Codes, blacks were not allowed to testify against whites, serve on juries or to vote. Blacks who did not sign yearly labor contracts with planters could be arrested. Some states limited job opportunities, barred them from acquiring land and even allowed judges to assign black children to work for their former owners without their parents consent.

Your answer is b , public works