What does Mr. Du Bois say has resulted from African Americans not insisting on political rights for 15 years?

This question seems to be incomplete. However, there´s enough information to find the right answer.

1. The disfranchisement of African Americans.

2. The establishment of a civil inferiority status for African Americans.

3. The decrease in educational aid for African Americans

Explanation:

In The Souls of Black Folk (Chicago, 1903),  W. E. B. Du Bois reacts to a speech by Washington, accusing him of calling for the submission of African Americans through conciliation, Du Bois explains that the reduced stress on the fight for political rights for African Americans that had occurred during the past 15 years had created the aforementioned effects.

wisdom

explanation:

the fact that that the teachings on the cosmic order comes from, or through, the heart center