The Freedmen's Bureau helped to secure the legality of formerly enslaved people in various ways, including:
A. citizenship: The Bureau helped formerly enslaved people to acquire legal citizenship status in the United States.
B. business ownership: The Bureau helped to provide resources and support for newly freed individuals to start their own businesses and become financially self-sufficient.
C. employment: The Bureau helped to provide employment opportunities and vocational training to newly freed individuals.
D. marriages: The Bureau helped to recognize and legalize marriages of formerly enslaved people, which had not been recognized under slavery.
D. Marriages is correct.