Answer: a.
providing educational opportunities for African Americans
Explanation:
The Freedman Bureau, which was established by an Act of Congress in 1865 was set up with the Noble intentions of helping the millions of poor blacks as well as poor whites in the former Confederate States of the United States.
Even though they were not very successful in their mission due to the politics that existed at the time involving race and social norms, they still managed to contribute immensely to Black education.
They were responsible for building thousands of schools for blacks and they helped found universities and colleges such as, Howard University (named after one of the original heads of the Freedman Bureau), Fisk University and Hampton University.
