Which of the following statements is true?
A. The principle of the conservation of mechanical energy states that the total
mechanical energy in a system remains constant as long as the only forces
acting are conservative forces.
B. Total energy is conserved for every system of particles on which there is an
external work done.
C. Some kinetic energy of an object will not be transformed into potential
energy and other forms of energy.
D. Total energy is not conserved for every system of particles