Final answer:
Aristotle believed that if something is moving, there must be a reason or cause for its movement (option c). This is distinct from Newtonian physics, where motion and changes in motion are ascribed to net external forces and is part of the broader philosophical stance that nothing can come into existence without a cause.
Step-by-step explanation:
According to Aristotle, if something is moving, there must be c) a reason or cause for its movement. This is rooted in the broader philosophical principle that nothing comes from nothing; hence, if there's something in existence, there must be a cause for it. Aristotle's philosophy extends to motion, where he posited the need for a First Mover or First Cause. This idea is crucial in the concept of causality in physics and differs from Newtonian physics, where motion requires a net external force to change a body's state of motion according to Newton's First Law, also known as the law of inertia.
On a related note, studying how forces affect the motion of objects is known as dynamics. External forces include those like friction, which opposes motion. Kinematics, by contrast, would simply describe how the object moves without delving into the causes.