This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Monitoring in Anesthesia, Subject name: Anaesthesia
[{'content': 'During CPCR in ACLS the waveform of capnograph shows following change. This indicates:- \nSelect and explain. \nA. Return of spontaneous circulation, B. Inadequate ventilation, C. Inadequate metabolism, D. Check position of Endotracheal tube', 'role': 'user'}, {'content': 'Answer: A \nExplanation: capnography is now an essential monitor in ACLS .', 'role': 'assistant'}]