This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Shoulder and arm injuries, Subject name: Orthopaedics
[{'content': 'which pa of Proximal humerus fracture has maximum chances of avascular necrosis? \nSelect and explain. \nA. One pa, B. Two pa, C. Three pa, D. Four pa', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Four pa fracture has a high incidence of avascular necrosis <img alt="" src=" /> Refer : maheshwari 9th ed', 'role': 'assistant'}]