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': 'Flat capnogram is seen in all except:- \nSelect and explain. \nA. Disconnection of endotracheal tube, B. Accidental extubation, C. Ventilation failure, D. Endobronchial intubation', 'role': 'user'}, {'content': 'Answer: D \nExplanation: A sudden drop of ET Co2 to near Zero followed by absence of a Co2 waveform heralds a potentially life threatening problem. Differential diagnosis D/d. 1. Malposition of an Endotracheal tube into the pharynx or oesophagus. 2. Circuit Disconnection 3. Stoppage of ventilation 4. Cardiac arrest 5. Massive pulmonary embolism', 'role': 'assistant'}]