This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Skeletal infections, Subject name: Orthopaedics
[{'content': 'Triple deformity of knee joint is seen in \nSelect and explain. \nA. Tuberculosis, B. Trauma, C. Malignant tumour, D. Sarcoidosis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: TB KNEE has two stages. In late stage it shows TRIPLE DEFORMITY- Posterior Subluxation External Rotation Flexion Other condition showing triple deformity of knee-Rheumatoid Ahritis REF : MAHESWARI 9TH ED', 'role': 'assistant'}]