What does Newton's Third Law explain about the interaction between two objects?

Newton's Third Law states that for every action, there is an equal and opposite reaction. This principle explains that when two objects interact, they exert forces on each other that are equal in magnitude but opposite in direction. For instance, if Object A pushes on Object B, Object B simultaneously pushes back on Object A with the same amount of force. This fundamental aspect of forces helps to explain various phenomena in mechanics, such as how rockets propel themselves as the engines push exhaust gases downwards, resulting in an upward thrust.

The other options do not align with this law: the first option incorrectly suggests that only one object exerts a force, which undermines the mutual nature of interactions. The second option claims that the forces are unequal, ignoring the essence of balance described by Newton's Third Law. Lastly, the third option implies that there are no reactions when objects interact, which directly contradicts the principle that every force has a corresponding reaction. Thus, understanding that both objects exert equal and opposite forces is crucial to grasping how interactions work in physics.