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': 'Endodermal cloaca gives rise to all of the following except - \nSelect and explain. \nA. Rectum, B. Lower 1/2 of anal canal, C. Upper 1/2 of anal canal, D. Mucous membrane of bladder', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Lower part of anal canal below the pectinate line develops from ectodermal invagination i.e. proctodeum.', 'role': 'assistant'}]