Why was Frederick Douglass important? He was the first governor of Kansas.
He made the first pro-slavery speech in Congress.
He was a leader of the abolitionist movement.
He led the movement for the Missouri Compromise.

it may be letter c, he was a slave that escaped and which sought to end the practice of slavery, before and during the Civil War.  so i'm not excactly sure of my answer but i do hope this is right!

 special committee worked out another compromise: Congress would have the power to ban the slave trade, but not until 1800. The convention voted to extend the date to 1808. A final major issue involving slavery confronted the delegates. Southern states wanted other states to return escaped slaves.

Explanation: