Which of the following statements about the use of hydrokinetic energy is not true?

a. hydrokinetic energy is a commonly used form of energy.

b. hydrokinetic energy requires the movement of waves.

c. hydrokinetic energy can be used without the need to mine materials.

d. hydrokinetic energy generates little waste.

Option A. i.e  Hydrokinetic energy is a commonly used form of energy is the correct answer.

This kind of energy is actually the electricity generated by harnessing the kinetic energy of tides and ocean or river currents. It requires high quality expensive turbine system to generate electricity and thus is not a commonly used form of energy.

a, i am pretty sure.