Question

the leader in the british abolition movement was
mary stewart.
frederick douglass.
william wilberforce.
olaudah equiano.

Explanation:

William Wilberforce was a key figure in the British abolition movement. He was a British politician who dedicated much of his life to the cause of ending the slave trade and slavery. Mary Stewart was a Scottish queen. Frederick Douglass was an American abolitionist. Olaudah Equiano was a writer and abolitionist but not the leader of the British abolition movement in the same sense as Wilberforce.

Answer:

William Wilberforce.