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': "Vertebra plana seen in -a) Eosinophilia granulomab) Traumac) Paget's diseased) Malignancye) Ewing's sarcoma \nSelect and explain. \nA. abcd, B. bcde, C. abde, D. ade", 'role': 'user'}, {'content': "Answer: C \nExplanation: Vertebra plana \n\nThis term is used to describe uniform collapse of a vertebral body into a thin, flat disc. The most common cause is eosinophilic granuloma, with the thoracic vertebrae most frequently affected. Causes are :-\n\n\nHistocytosis - X (Eosinophilic granuloma)\nLeukemia\nTB\nMetastasis, Multiple myeloma, Ewing's sarcoma, lymphoma\nOsteochondritis of vertebral body (Calve's disease)\nHemangioma\nTrauma\nSteroids", 'role': 'assistant'}]