Q: A ball is moving on a horizontal table with some velocity. It stops on its own after moving some distance. Which external force(s) cause(s) change in the linear momentum of the ball (ignore air)?
A: The ball loses momentum due to two effects:
Friction due to some slipping between the ball and the table.
Deformation of the ball and/or the table during rolling, which shifts the line of action of the normal reaction slightly ahead of the vertical through the centre. This gives the contact force a small backward horizontal component (rolling resistance), which opposes the motion and reduces the ball's momentum.