The pupil opens and closes automatically in response to light. what part of the nervous system controls this response? explain whether this is voluntary or involuntary action

The pupil controls the intensity of light entering into the eye.

The parasympathetic branch of the autonomic nervous system (PSNS) controls the constriction of the pupil and the sympathetic branch of the autonomic nervous system controls the dilation of the pupil.

It is an automatic action which translates to it being an involuntary action.