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: Surgery
[{'content': 'Pencil in cup deformity is seen in ? \nSelect and explain. \nA. Rheumatoid ahritis, B. Ankylosing spondylitis, C. AVN, D. Psoriatic ahritis', 'role': 'user'}, {'content': "Answer: D \nExplanation: Ans. is `4:1' i.e., Psoriatic ahritis Impoant", 'role': 'assistant'}]