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': "Lower 1/3'd of anal canal is derived from? \nSelect and explain. \nA. Proctodaeum, B. Cloaca, C. Urogenital Sinus, D. Midgut", 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is'a'i.e., Proctodaeum(Ref: BDC Sh/eVol. Il p. 415)'The lower third of the anal canal is an ectodermal derivative and is derived from the proctodaeum.'Pa of anal canal above pectinate line develops from dorsal pa of md.odermal cloaca (primitive rectum) and pa of anal canal below pectinate line develops from ectodermal proctodeum.", 'role': 'assistant'}]