This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Arthritis, Subject name: Orthopaedics
[{'content': 'Osteoarthritis does not affect: \nSelect and explain. \nA. Knee joint, B. Hip joint, C. Interphalangial joint, D. Metacarpophalangial joint', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans: d (Metacarpophalangeal joint)Ref: Maheshwari Ortho, 3rd ed, p. 252 & Harrison, 15thed, p. 1990', 'role': 'assistant'}]