This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Otitis Media, Subject name: ENT
[{'content': 'Ca Wheel sign is seen in: \nSelect and explain. \nA. ASOM, B. Glomus, C. OME, D. CSOM', 'role': 'user'}, {'content': 'Answer: A \nExplanation: In ASOM, the TM appears very red and congested. Since the vessels on the TM run radially this hyperaemic appearance is also known as Ca wheel appearance of TM', 'role': 'assistant'}]