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: Medicine
[{'content': 'Proximal interphalangeal, distal interphalangeal & 1st carpometacarpal joint involvement and sparing of wrist is a feature of: \nSelect and explain. \nA. Rheumatoid ahritis, B. Pseudogout, C. Psoriatic ahropathy, D. Osteoahritis', 'role': 'user'}, {'content': "Answer: D \nExplanation: Answer is D (Osteoahritis) :Sparing of wrist and metacarpophalangeal joint with involvement of base of thumb (i.e. carpometacarpal joint) is very characteristic of `osteoahritis'.Both DIP (Herbeden's nodes) and PIP (Bouchard's nodes) are involved in osteoahritis.QDIP is the most common form of idiopathic O.A.", 'role': 'assistant'}]