B) Radical Republicans thought Johnson was too harsh toward the South.
Johnson's refusal to support the legislation that had united the Republican majority in Congress proved fatal to his program, for it had driven the moderates into the Radical camp. ... By passing the Civil Rights Bill, the Republicans had shown their commitment to civil rights for blacks.
You could talk about it's past and/or it's ancient civilizations. You could also possibly compare it's old civilization to it's current one, talk about the changes.
A. Social Issues because the different races were disliked socially, and caused further fear politically as well. But it originated as a social problem.
