A 3-month-old female infant is diagnosed with anal stenosis after several periods of stool infrequency, two of which lasted 10 days without a bowel movement. Which of the following is the most likely cause of this condition?

Dorsal deviation of the urorectal septum results in anal stenosis. Incomplete separation of the cloaca by the urorectal septum results in anal agenesis. Failure of the anal membrane to perforate results in imperforate anus. The anal canal exists but is obstructed by a layer of tissue. Abnormal recanalization of the colon results in rectal atresia, in which there is no connection between the rectum and anal canal. Remnants of the proximal portion of the omphaloenteric duct would result in a Meckel diverticulum, not anal stenosis.