This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolic and endocrine disorders, Subject name: Orthopaedics
[{'content': "Calcification of interveebral disc is a feature of \nSelect and explain. \nA. Ankylosing spondylitis, B. Hyperparathyroidism, C. Charcot's disease, D. Alkaptonuria", 'role': 'user'}, {'content': 'Answer: D \nExplanation: xray of ochronosis in alkaptonuria is seen symtpoms of alkaptonuria : SYMPTOMS * Urine becomes black when exposed to air. * Osteoahritis (mainly spine, hips, shoulders and knees). * Black spots in the sclera of the eye (Ochronosis). * Discolored ear and dark earwax. * Hea valves are affected by the accumulation of HGA. * Blue-black speckled discoloration of the skin. * Kidney, prostate and bladder stones due to the build-up of HGA in the genito-urinary tract, during urine production. ref : maheswari 9th ed', 'role': 'assistant'}]