This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Gastrointestinal tract, Subject name: Pediatrics
[{'content': 'Chronic constipation in children is seen in all A/E \nSelect and explain. \nA. Hirschspring disease, B. Jejunal polyp, C. Hypothyroidism, D. Stricture', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Causes of constipation : Intestinal drugs metabolic neuromuscular others hirschsprung,sdisease anal stenosis anal fissure anteriorly displaced anal opening stricture narcotics vincristine psychotropics cystic fibrosis hypothyroidism panhypopituitarism cerebral palsy psychomotor retardation spinal cord lesions myotonic dystrophy neuropathy or myopathy of GIT low fibre diet milk protein allergy Ref : ESSENTIAL PEDIATRICS,O.P.GHAI,PG NO:255', 'role': 'assistant'}]