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': 'All are true about thoracic duct except- \nSelect and explain. \nA. Begins as continuation of cisterna chyli, B. Passes through the esophageal opening, C. Ends into junction between left subclavian and internal jugular vein, D. Largest lymphatic vessel', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Thoracic duct pierces the diaphragm and passes to posterior mediastinum through aortic opening.', 'role': 'assistant'}]