This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Disorder of Metabolism & Connective Tissue, Subject name: Medicine
[{'content': 'Joint not involved in Rheumatoid arthritis? \nSelect and explain. \nA. D.I.P, B. P.I.P, C. M.C.P, D. Wrist', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans.(a) D.I.PRef : Harrison 19th ed. / 2142* Rheumatoid arthritis characteristically causes swelling of small joints in the hand like the P.I.P, M.C.P and the wrist joint bilaterally.* Isolated D.I.P joint involvement is seen in psoriatic arthropathy.* D.I.P joint involvement is also seen with osteo-arthritis but the involvement is with pain at the base of thumb. Knee joint is the commonest joint involved in these patients.', 'role': 'assistant'}]