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': 'True about endotracheal intubation is: \nSelect and explain. \nA. It reduces normal anatomical dead space, B. It produces decrease in resistance to respiration, C. Subglottic edema is most common complication, D. All of the above', 'role': 'user'}, {'content': 'Answer: A \nExplanation: A i.e. It reduces the normal anatomical dead space - Endotracheal tube decreases the anatomical dead space (150 ml) to as less as 25 ml. - Endotracheal intubation increases the resistance to respiration; obstruction from kinking, foreign body or secretions fuher increase resistance. Subglottic edema, though a complication, is not the most common one.', 'role': 'assistant'}]