This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous General Anesthesia, Subject name: Anaesthesia
Which gas is most commonly used in laparoscopy: 
Select and explain. 
A. O2, B. CO2, C. N2O, D. N2
B: CO2
Answer: B: CO2 
Explanation: Ans. is 'b' CO2