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
Treatment of choice of flail chest chest is 
Select and explain. 
A. External fixation of flail segment and mechanical ventilation, B. Strapping, C. O2 administration, D. Intrapleural local analgesia
C: O2 administration
Answer: C: O2 administration 
Explanation: None