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: Orthopaedics
[{'content': 'Which is not involved in Ankylosing spondylitis - \nSelect and explain. \nA. Knee & Ankle, B. Sacroilac Jt., C. Wrist & elbow, D. Spine', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Joints involvement in AS\nSacroiliac > spine & costovertebral > Hip > shoulder > knee > ankle', 'role': 'assistant'}]