This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nose and paranasal sinuses, Subject name: ENT
[{'content': 'If posterior epistaxis cannot be controlled,which aery is kigated \nSelect and explain. \nA. posterior Ethmoidal aery, B. Maxillary aery, C. Sphenopalatine aery, D. External carotid aery', 'role': 'user'}, {'content': 'Answer: C \nExplanation: ESPAL is the current ligation of choice controlling bleeding in over 90% of cases with a low complication rate. Sphenopalatine aery is ligated in the sphenopalatine foramen. Ref Scott Brown 7/e,Vol 2,p 1606.', 'role': 'assistant'}]