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': 'Bleeding ear discharge is mostly due ? \nSelect and explain. \nA. Glomus tumour, B. Otosclerosis, C. Otitis media with effusion, D. Acoustic neuroma', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is'a'i.e., Glomus tumour(Ref: Dhingra 6h/e p. 109)", 'role': 'assistant'}]