Which sentence from the article BEST supports a central idea?
(A) African-Americans had endured centuries of slavery and the struggle to do away with it.
(B) Though poor, Harlem also had an educated class who made Harlem a center of culture.
(C) Actor and singer Paul Robeson electrified audiences with his stage performances.
(D) Thousands of city dwellers flocked night after night to see the same performers.