Final answer:
Frederick Douglass was an abolitionist who wanted to abolish slavery (A) in the United States. He was a key figure in the reform movement against slavery and fought for equality and civil rights for African Americans, even after the Civil War.
Step-by-step explanation:
Frederick Douglass was an abolitionist, which meant he wanted to abolish, to end slavery. Douglass, born a slave in Maryland and later a prominent voice in the abolitionist movement, tirelessly worked to end the institution of slavery in the United States. The answer to the question is A) Slavery.
Abolitionists, like Douglass, advocated for a reform movement calling for the complete end to slavery, opposing views such as colonization which allowed for the gradual end of slavery. Using moral arguments, they highlighted the immorality of slavery and supported creating a multiracial society of equals. Even after the Civil War and the end of slavery with the Emancipation Proclamation, Douglass continued to fight for black equality and civil rights, recognizing that legal freedom did not guarantee social or economic equality.