This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thoracic and Lumbosacral Spine Injuries, Subject name: Orthopaedics
[{'content': 'Holdsworth classification of thoracolumbar spine fracture is based on how many columns of spine? \nSelect and explain. \nA. Two, B. Three, C. Four, D. Five', 'role': 'user'}, {'content': 'Answer: A \nExplanation: ANSWER: (A) TwoREF: Harris Ik Harris\' The Radiology of Emergency" Medicine By Thomas L. Pope 5th ed page 272, Rockwood 7th ed ch: 43, Spinal Trauma: An Imaging Approach By Victor N. Cassar- Pullicino, Herwig Imhof page 56One of the first descriptions of fractures of the thoracolumbar spine was put forth by Sir Frank Holds worth in 1953.See details of Dennis\' three-column concept of spine in Radiology 2012 Session 2', 'role': 'assistant'}]