Consider the Assertion and the Reason, and choose the correct option.
Assertion [A]: All muscles follow “all or none” principle.
Reason [R]: If a stimulus is above a certain threshold, a nerve or muscle fiber will fire.
Both Assertion [A] and Reason [R] are True and [R] is a correct explanation for [A]
The all-or-none law is the principle that the strength by which a nerve or muscle fiber responds to a stimulus is independent of the strength of the stimulus. If that stimulus exceeds the threshold potential, the nerve or muscle fiber will give a complete response. Otherwise, there is no response.