The correct answer is A. Racial injustice in the post-Civil War era
Step-by-step explanation:
W.E.D. Du Bois was an American civil rights activist and writer, indeed during his life, Du Bois supported equal rights for blacks and opposed discrimination and laws that were against them. Besides this, he was mainly known for his essays "The Souls of Black Folk" and "Black Reconstruction in America" to show racial injustice after the Civil War as well as the role of black people in the reconstruction.
On the other hand, Booker T. Washington was an educator and author that supported rights for blacks but different to Du Bois he considered equality could be achieved through entrepreneurship rather than directly attacking laws against discrimination. Additionally, like Du Bois, he wrote about racial injustice in the time especially in his book Up from Slavery. Thus, both authors wrote about their experiences to expose racial injustice in the post-Civil War era.