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: Orthopaedics
[{'content': 'Treatment of choice in 65-year-old female with impacted # neck of the humerus is - \nSelect and explain. \nA. Triangular sling, B. Arm chest strapping, C. Arthroplasy, D. Observation', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Impacted fracture of surgical neck humerus is treated by rest of the arm in triangular sling.', 'role': 'assistant'}]