Final answer:
Booker T. Washington's Atlanta Compromise speech and his stance on accommodation validate Du Bois' criticism about accepting racial inferiority for practical gains, which is seen as perpetuating white supremacy.
Step-by-step explanation:
W.E.B. Du Bois' criticism that Booker T. Washington "practically accepts the alleged inferiority of the Negro races" can be attributed to Washington's Atlanta Compromise speech, where he suggests a form of acceptance of segregation in return for the industrial progress of African Americans. Washington's approach, as Du Bois points out, could be seen as an accommodation to white supremacy for practical gains. It is this strategic accommodation that Du Bois criticizes, arguing that it may perpetuate the notion of African American inferiority and diverts responsibility for the 'Negro problem' away from the nation and onto the Negro's shoulders. Washington's program being described as a gospel of Work and Money further suggests that he prioritized economic development over civil rights advocacy.