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': 'At what angle is hallpike thermal caloric test done - \nSelect and explain. \nA. 15°, B. 30°, C. 45°, D. 60°', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]