Answer:
D) Acceleration
Step-by-step explanation:
Force is an agent that can stop or tend to stop a moving object and can produce or tend to produce motion in a body at rest.
A balanced force is equal in magnitude and acting in opposite direction that cause no change in the state of rest or motion.
But UNBALANCED FORCE is not equal in magnitude and/or opposite, so it changes the speed and/or direction in the moving bodies result in producing acceleration in the objects.