This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Pediatrics
[{'content': 'Umbilical cord has ____________ \nSelect and explain. \nA. 1 vein and 2 aeries, B. 2 vein and 2 aeries, C. 1 vein and 1 aery, D. 2 veins and 1 aery', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Umbilical cord contain two aeries & one vein. Ref : Ghai essential of pediatrics, 19th edition, p.no402 ; Davidson principal and practice of internal medicine, 22nd edition, p.no:630', 'role': 'assistant'}]