A thin circular ring of mass M and radius R is rotating in a horizontal plane about an axis vertical to its plane with a constant angular velocity o. If two objects each of mass m be attached gently to the opposite ends of a diameter of the ring, the ring will then rotate with an angular velocity: (a) (b) (c) (d) wM M+2m w(M+2m) M M M+m w (M-2m) M+2m