This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Operative Gynecology, Subject name: Gynaecology & Obstetrics
[{'content': 'The best gas used for pneumoperitoneum laparoscopy is \nSelect and explain. \nA. N2, B. O2, C. CO2, D. NO', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Carbon dioxide is the most widely used peritoneal distention medium, because it is non-flammable, colourless and has a higher blood solubility than air & the rapid absorption of CO2 in blood reduces the incidence of gas emboli.', 'role': 'assistant'}]