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: Surgery
[{'content': 'Head shaking test is done to diagnose \nSelect and explain. \nA. Maxillary sinusitis, B. Vertigo, C. Position of root in relation to maxillary antrum, D. Maxillary fracture', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]