Question W. Du Bois is famous for having said this about the 20th century in the United States:

Question W. E. B. Du Bois is famous for having said this about the 20th century in the United States: my answer is B

A) Despite setbacks, caste and color would not be the main problem in race relations.

B) The main problem would be "the problem of the color line."

C) The main problem for African Americans would be socioeconomic advancement.

D) In the 20th century, people would be assessed "by the contents of their character rather than the color of their skin."