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
What happens to ETCO2 on increasing rate and depth of breathing 
Select and explain. 
A. Increases, B. Decreases, C. Remain high, D. No change
B: Decreases
Answer: B: Decreases 
Explanation: None