This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Other Rheumatic Diseases, Subject name: Orthopaedics
[{'content': 'Joint not involved in osteoarthritis - \nSelect and explain. \nA. PIP, B. DIP, C. MCP, D. Knee', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., MCP Joint involvement in OAo Common joints : Knee, Hip, Spine (cervical, lumbosacral), Hand (PIP, DIP, first carpometacarpal), first tarso-metatarsal.o Uncommon joint: Shouldero Spared: Wrist, elbow, ankle, metacarpophalangeal.", 'role': 'assistant'}]