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: ENT
[{'content': 'A tracheostomised patient, with Portex tracheostomy tube, in the ward, developed sudden complete blockage of the tube. Which of the following is the best next step in the management - \nSelect and explain. \nA. Immediate removal of the tracheostomy tube, B. Suction of tube with sodium bicarbonate, C. Suction of tube with saline, D. Jet ventilation', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]