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': 'Joints of hand are not affected in- \nSelect and explain. \nA. AS, B. RA, C. OA, D. Psoriatic arthritis', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e.. AS o Ankylosing spondylitis does not affect hand and foot joint,o OA, RA and psoriatic arthritis affect hand joints.Joints involvedDiseasesPIPRA, OA, Psoriatic arthritisPIP + DIPOA, Psoriatic arthritisPIP + DIP + 1st carpometacarpal joint with sparing of MTP & wristOAPIP + MTP + wrist with sparing of DIPRAPIP+DIP+MTP+wrist (However any joint can be spared)Psoriatic arthritisAxial joints (SI joint, spine), Hip, shoulderAnkylosing spondylitis", 'role': 'assistant'}]