Why Did the North Enact a Blockade on the Confederacy

Why did the North enact a blockade on the Confederacy during the Civil War?

A) To persuade them to rejoin the Union
B) To deny them the imports they needed to survive
C) To stop the shipment of cotton to France to get them to join the war
D) To attack Washington, D.C.undetected
E) To divert the goods shipped overseas to internal markets