Assume that the pendulum clock shown in the photograph is a closed system
Which statement describes evidence that the pendulum's energy is conserved
even as it eventually stops moving?
A. Energy must be added to the pendulum to keep it from slowing
down
B. Some of the clock's matter is transformed into new energy
C. The amount of each type of energy in the system can be
measured
D. All its mechanical energy is transformed into other forms of
energy