Final answer:
Option (B), The muscle's immediate contraction in response to being stretched too quickly is known as the stretch reflex or myotatic reflex. It is a protective response designed to maintain muscle length and prevent overstretching.
Step-by-step explanation:
If a muscle is stretched too quickly, the muscle responds with an immediate contraction to stop the stretch. This specific action is called the stretch reflex, also known as the myotatic reflex. This reflex involves the activation of muscle spindle receptors, which then send a signal through the axon causing the muscle to contract and inhibit the antagonist muscles' motor neurons.
This mechanism is a protective response to prevent muscles from stretching too far and helps to maintain constant muscle length. An everyday example of this is the knee-j_erk reaction observed during a physical exam.