Answer:
All the processes given involves the conversion of potential energy to kinetic energy
Step-by-step explanation:
The kinetic energy is the energy possessed by an object because of its motion, equal to one half the body's mass times the square of its speed.
i.e

On the other hand, The potential energy is the energy possessed by an object because of its position in a gravitational or electric field, or its condition as a stretched or compressed spring, as a chemical reactant,or by having rest mass.
SO, from both definitions :
Water cascades downward in a waterfall → involves the conversion of potential energy to kinetic energy
A player kicks a football → involves the conversion of potential energy to kinetic energy
An electric current is generated by a chemical reaction in a battery. → involves the conversion of potential energy to kinetic energy
Water boils when heated on a gas stove. → involves the conversion of potential energy to kinetic energy