Which was an effect of the Supreme Court case Plessy v. Ferguson?

A.
It reaffirmed and strengthened Jim Crow laws in the South.
B.
It weakened and outlawed Jim Crow laws in the North.
C.
It reduced the frequency of racial violence in the South.
D.
It caused increased migrations of people from the North.

A. It reaffirmed and strengthened Jim Crow laws in the South.