Which of the following is the best definition of energy? A. the ability to generate electricity B. the ability to generate heat C. the ability to do work D. the ability to produce fusion

The phrase that best describe the word "energy" is letter "C. the ability to do work". The unit most commonly used to express energy is Joules (J) which is also derived from the equation of work which is the product of force and the distance that a body moves parallel to the force applied.

C) The ability to do work is the best definition of energy among these options.