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': 'Abbey Estlander flap is based on: \nSelect and explain. \nA. Lingual artery, B. Facial artery, C. Labial artery, D. Internal maxillary artery', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]