How did the ruling in Plessy v. Ferguson contribute to the phenomenon shown in the map?
A. A rise in southern segregation laws spurred African Americans to abandon areas with legalized discrimination
B. The loss of voting protections in the south prompted African Americans to emigrate to secure equal rights
C. Tolerance of lynchings among southern states encouraged African Americans to seek safer communities
D. The legality of southern sharecropping that kept African Americans poor led them to speak new job opportunities
