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: ENT
[{'content': 'Cartilagenous part of external auditory canal is - \nSelect and explain. \nA. Medial 1/3, B. Lateral 1/3, C. Medial 2/3, D. Lateral 2/3', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]