Final answer:
Extensibility refers to the ability of a muscle to stretch or extend in response to a stimulus, leading to muscle contraction.
Step-by-step explanation:
True.
Extensibility refers to the ability of a muscle to stretch or extend in response to a stimulus. When a muscle receives a nervous stimulus, it increases in tension or decreases in length, resulting in muscle contraction. This allows the muscle to pull on its attachment points and shorten with force.