Why is kinetic energy the answer for energy of motion?

Answer 1

Because the definition of "kinetic" energy is the Energy of [atomic] motion.

Answer 2

Kinectic is energy is basically the energy of action. Potential energy is the possibility for action. Mechanical energy is basically the energy of movement and movement is an action.

Answer 3

Mechanical energy is the energy possessed because of the motion and position of an object. Sound is the vibration (motion) of particles.