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': 'Which of the following statements are true about Flail chest? 1. Fracture of 3 or 4th ribs 2. Mechanical ventilation always needed 3. Mediastinal shift 4. Inward movement of chest wall during inspiration 5. Ultimately leads to Respiratory failure \nSelect and explain. \nA. 3,4,5 True & 1,2 False, B. 3,4,5 False & 1,2 True, C. 1,4,5 True & 2,3 False, D. 1,2,4 False & 3,5 True', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Fracture of 3 or 4th ribs and inward movement of chest wall during inspiration are seen in Flail chest. It will ultimately leads to respiratory failure.', 'role': 'assistant'}]