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': 'Bifurcation of trachea is at the level of lower border of: \nSelect and explain. \nA. T1, B. T2, C. T3, D. T4', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. D i.e. T4', 'role': 'assistant'}]