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: Anaesthesia
Most common cause for end tidal CO2 falls due to – 
Select and explain. 
A. Cardiac arrest, B. Extubation, C. Hypothermia, D. Hyperhennia
B: Extubation
Answer: B: Extubation 
Explanation: Most common cause of fall in ET CO2 is accidental extubation.