When a muscle is unable to respond to stimuli temporarily, it is in which of the following periods?

A) latent period

B) fatigue period

C) relaxation period

D) refractory period

refractory period is the correct answer.

Explanation:

A refractory period happens when the muscle and nerve are unable to respond to the additional stimulation temporarily.

A refractory period occurs because sodium ions channels are not activated during this period.

The refractory period differs among the individuals, it ranges from minutes to a day.

During this period many are temporarily not interested in sexual activity and their penis can be hypersensitive or some of the men are not able to sustain an erection during this period.