The correct option is B Friction
Friction opposes the relative motion between the surfaces in contact with each other.
Friction is the force that opposes relative motion or tendency of relative motion between two surfaces in contact. When two surfaces move relative to each other or they have a tendency to move relative to each other, at the point (or surface) of contact, there appears a force which opposes this relative motion or tendency of relative motion between two surfaces in contact. It acts on both the surfaces in contact with equal magnitude and opposite directions (Newton's 3rd law). also Friction force tries to stop relative motion between two surfaces in contact.