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': 'Most appropriate investigation for angiofibroma is - \nSelect and explain. \nA. Angiography, B. CT scan, C. MRI scan, D. Plain X- ray', 'role': 'user'}, {'content': 'Answer: B \nExplanation: CT scan of the head with contrast:- is the investigation of choice. It shows the extent of tumor, bony destruction, or displacement. Anterior bowing of the posterior wall of maxillary sinus (antral sign or Holman-Miller sign) is pathognomonic of JNA.', 'role': 'assistant'}]