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
[{'content': 'Capnography basically monitors - \nSelect and explain. \nA. Central venous pressure, B. Blood pressure during anesthesia, C. Concentration of exhaled CO2, D. Concentration of inhaled O2', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Capnography is the continuous measurement of end-tidal CO2 (ETCO2), i.e. the CO2 in expired air.', 'role': 'assistant'}]