Which of the following statements is true?

AThe 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.

BTotal energy is conserved for every system of particles on which there is an

external work done.

CSome kinetic energy of an object will not be transformed into potential

energy and other forms of energy.

DTotal energy is not conserved for every system of particles