What is the correct interpretation of Newton's Third Law?

Newton's Third Law states that for every action, there is an equal and opposite reaction. This principle emphasizes the mutual interactions between two bodies: when one body exerts a force on another, the second body exerts a force of equal magnitude in the opposite direction back on the first body. This law explains a wide range of phenomena, from how rockets propel themselves by expelling gas downwards to the way a swimmer pushes water backwards to move forward. Understanding this relationship is crucial in mechanics, as it lays the foundation for analyzing forces and motions in both static and dynamic systems.

The other options do not accurately capture this law's essence. For instance, saying that action and reaction forces do not affect motion ignores the fundamental nature of interactions and the role they play in changing an object's state of motion. The statement about exerting force to stop an object's motion does not account for the nuance of forces and is overly simplistic. Lastly, the idea that an object in motion will stay in motion refers to Newton's First Law, which deals with inertia rather than the interplay of forces described in the Third Law.