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': 'Rugger jersey spine in CRF is due to - \nSelect and explain. \nA. Osteomalacia, B. Trauma, C. Hyperparathyroidism, D. Aluminium osteodystrophy', 'role': 'user'}, {'content': 'Answer: C \nExplanation: A common finding in secondary hyperthyroidism associated with renal osteodystrophy is the osteosclerosis resulting in typical appearance of the vertebral bodies as seen in the rugger - jersy spine.', 'role': 'assistant'}]