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 internal thoracic veins are tributaries of the : \nSelect and explain. \nA. Azygos, B. Subclan, C. Internal jugular, D. Brachiocephalic', 'role': 'user'}, {'content': 'Answer: D \nExplanation: D i.e. Brachio cephalic vein', 'role': 'assistant'}]