This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thorax And Mediastinum, Subject name: Surgery
Which of the following are boundaries of Poirier's Triangle? 
Select and explain. 
A. Arch of aoa, B. Left subclan aery, C. Veebral column, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: Poirier's Triangle . Boundaries: - Inferior-Arch of Aoa - Anterior- Left subclan aery - Posterior- veebral column Impoance- Identification of thoracic duct.