This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Joint disorders, Subject name: Orthopaedics
[{'content': 'Which of the following is difference between Rheumatoid ahritis and osteoahritis? \nSelect and explain. \nA. Osteophytes are seen in osteoahritis, B. Systemic symptoms are seen in osteoahritis, C. Rheumatoid ahritis is uncommon in hands and feet, D. Osteoahritis is an autoimmune disease', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Rheumatoid Ahritis Knee Osteoahritis Knee Periaicular osteopenia Subchondral sclerosis Valgus > Varus Varus > valgus Marginal erosions Marginal erosions not seen No osteophytes are seen Osteophytes are seen Soft tissue swelling (pannus) Negative Subchondral cysts Subchondral cysts Figs. (A) RA Knee-Genu valgus; (B) OA Knee-Genu varus', 'role': 'assistant'}]