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': "Which of the following is the SAFEST test to be performed in a patient with acutely injured knee joint - \nSelect and explain. \nA. Lachmann test, B. Pivot shift test, C. McMurray's test, D. Apley's grinding test", 'role': 'user'}, {'content': "Answer: A \nExplanation: Pivot shift test and anterior drawer test require flexion of the knee joint, which cannot be possible in acutely injured knee.\nLachman's test is done in 15-30° of flexion, therefore can be performed in acutely injured knee.", 'role': 'assistant'}]