The Following Questions Refer to the Excerpt Below

The following questions refer to the excerpt below.
"… Of all the races and varieties of men which have suffered from this feeling,the colored people of this country have endured most… The African origin can be instantly recognized,though they may be several removes from the typical African race…They are Negroes-and that is enough,in the eye of this unreasoning prejudice,to justify indignity and violence.In nearly every department of American life they are confronted by this insidious influence…It meets them at the workshop,and factory,when they apply for work.It meets them at the church,at the hotel,at the ballot box,and worst of all,it meets them in the jury box… Everything against the person with the hated color is promptly taken for granted;while everything in his favor is received with suspicion and doubt."
Frederick Douglass,The Color Line,1891
-Which of the following developments most directly supported the central argument made by Douglass?

A) Expanded scientific research on race theories worked to benefit African Americans.
B) Radical Republicans in Congress focused their efforts on reforming the Constitution.
C) African Americans saw an erosion of the political gains they had made during Reconstruction.
D) Advocates of the social gospel worked to make improvements to U.S. race relations.