Which of the following would not inhibit micturition?

A) stimulation of the somatic motor neurons to the external urethral sphincter

B) activation of the sympathetic pathways

C) relaxation of the internal urethal sphincter

D) relaxation of the detrusor muscles

C) relaxation of the internal urethal sphincter

Explanation:

The muscles that control micturition are controlled by the autonomic and somatic nervous systems.

Micturition is inhibited (storage phase, when bladder is at low volume) when internal urethral sphincter are contracted and the detrusor muscle relaxed by sympathetic stimulation. During micturition, parasympathetic stimulation leads to the detrusor muscle contraction and the internal urethral sphincter relaxation. The external urethral sphincter is under somatic control and is consciously relaxed during micturition.