This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Lower limb, Subject name: Anatomy
[{'content': 'Vein used to bypass the coronary aery \nSelect and explain. \nA. Long saphenous vein, B. Sho saphenous vein, C. Soleal vein, D. Tibial vein', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Varicose veins are due to the touosity of the long saphenous vein and occur mostly due to prolonged standing.The long saphenous vein is used to bypass the coronary aery after inveing the vein.Ref: Chaurasia; Volume 2; 6th edition; Page no: 135', 'role': 'assistant'}]