A Newborn Boy Does Not Pass Meconium in the First

Multiple Choice

A newborn boy does not pass meconium in the first 24 hours. His abdomen is distended, and he begins vomiting. Various other tests lead to a diagnosis of Hirschsprung's disease. An obstruction is most likely to be found in which portion of the gut?

A) Ascending colon
B) Ileocecal sphincter
C) Lower esophageal sphincter
D) Pylorus
E) Sigmoid colon