Which Statement Does NOT Describe the Defecation Reflex

Multiple Choice

Which statement does NOT describe the defecation reflex

A) initiated when mass movements force fecal material into the rectum, stimulating stretch receptors in the rectal wall
B) involves relaxation of the internal anal sphincter
C) cannot be overridden by voluntary contraction of the external anal sphincter
D) involves contraction of the sigmoid colon and rectum