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': "A full thickness loss of middle one third of the upper lip is best reconstruted by -a) Naso labial flapb) Cheek flapc) Abey flapd) Estlander's flap \nSelect and explain. \nA. cd, B. bc, C. bd, D. ac", 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]