The answer is: D) the African-American Civil Rights movement.
Eversince the abolishment of which initiated by Abraham Lincoln, United States still struggle to granted rights for the African American people, even though technically they are no longer owned slaves.
These lead to decades long of African-American Civil rights movement, which the purpose of granting human rights for African American Citizens in united States.
The movements eventually led to the creation of Civil Rights Act in 1964, which legally banned all forms of discrimination based on race, color, religion, sex.
Because of this acts, Even though intiially the movements were targeted for the African Americans, Women and other minorities also experienced expansion of equality in the society.