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: Anatomy
[{'content': 'The structure related to arch of aoa is: \nSelect and explain. \nA. Left bronchus, B. Tracheal bifurcation, C. Ligament of teres, D. Right Vagus', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Tracheal bifurcation', 'role': 'assistant'}]