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': 'Oxygenated blood from fetus is carried by: \nSelect and explain. \nA. Umbilical artery, B. Umbilical vein, C. Ductus venosus, D. Hypogastric artery', 'role': 'user'}, {'content': "Answer: B \nExplanation: b. Umbilical vein(Ref: Nelson's 20/e p 2161-2162, Ghai 8/e p 402)Blood oxygenated in placenta returns via umbilical vein, which enter the fetus at the umbilicus and joins portal vein", 'role': 'assistant'}]