4. Consider a collision between two objects. Which one of the following statements is wrong?
(A) If the collision is elastic, the total kinetic energy is conserved after the collision.
(B) If the collision is elastic, the total momentum is conserved after the collision.
(C) If the collision is inelastic, the internal energy of these two objects may increase.
(D) If the collision is inelastic, the total momentum is not conserved after the collision.
(E) If the collision is inelastic, the total kinetic energy is not conserved after the collision.