A Child Swinging on a Swing Utilizes Which Type(s) of Energy

A child swinging on a swing utilizes which type(s) of energy?

A) kinetic energy only because the child is in constant motion
B) potential energy only, because the child has to invest energy to get the swing to move
C) chemical energy only, because it is the child's metabolism that powers the muscles that make the swing move
D) kinetic and potential energy only, but in constantly changing ratios: when changing direction, it is pure potential energy; at the bottom of the arc, it is pure kinetic energy
E) kinetic, potential, and chemical energy: the child powers the swing with chemical energy in the muscle, cells and the swing moves like a pendulum with changing ratios of kinetic and potential energy.