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: Surgery
[{'content': 'Any cuffed tube that is passed into trachea should reach: \nSelect and explain. \nA. Above vocal cords., B. Below vocal cords., C. At the level of vocal cords., D. Any of the above.', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]