The capacity to do work is called:

Energy is the fundamental capacity to do work, which is defined as the transfer of energy that occurs when a force is applied over a distance. This foundational concept in physics explains that any action requiring effort or causing a change in state involves energy. Therefore, option A is precisely accurate.

• Force (B) is a push or pull that can cause an object to accelerate, but it is not the capacity to do work itself; it is what performs the work.
• Motion (C) is the act of changing position or location, which is often a result of work being done, rather than the capacity to do it.
• Momentum (D) is a measure of the mass and velocity of an object, indicating its quantity of motion, but it does not represent the inherent capacity to perform work.