According to newton's third law, forces come in pairs. there is and an equal and opposite

Reaction is the correct answer.

Explanation:

Newton's third law stated that for every action there is an equal and opposite reaction. It means that when a pair of forces are acting on two objects which are interacting with each other, the force of the first object is equal to the force on the second object and the direction of the force on the first object is opposite the force on the second object. Hence, it can be said that force always comes in pairs, the pair include action and reaction, which are opposite to each other. Recoiling of the rifle is the example of Newton's first law of motion.

stimulus is a change in the environment that causes an organism to react. the response is the reaction to the stimulus. some examples of stimuli for zebras are drought, to many predators, and bad feeding grounds such as dead grass or plants. zebras respond to stimuli just like all other living organisms