This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Injuries to the Leg, Ankle & Foot, Subject name: Orthopaedics
[{'content': 'Hawkin sign denotes? \nSelect and explain. \nA. Retained vascularity, B. Non union, C. Decrease vascularity, D. Avascular necrosis', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. (a) Retained vascularityRef:Rockwood and wilkins' Fractures in children p 1020y Lovell and winter's pediatric orthopaedics vol-l, 6/e,p 1512)", 'role': 'assistant'}]