This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Anatomy
[{'content': 'Failure of migration of neural crest cells is seen in? \nSelect and explain. \nA. Albinism, B. Congenital megacolon, C. Odontomes, D. Adrenal tumour', 'role': 'user'}, {'content': 'Answer: B \nExplanation: B i.e. Congenital Megacolon', 'role': 'assistant'}]