This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thorax, Subject name: Anatomy
[{'content': 'Superior vena cava opens into right atrium at the level of \nSelect and explain. \nA. T1, B. T3, C. T4, D. T5', 'role': 'user'}, {'content': 'Answer: D \nExplanation: SVC open into right atrium at the level of T5 . Ref - BDC 6th edition vol 1 pg272', 'role': 'assistant'}]