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: Gynaecology & Obstetrics
[{'content': 'The finding of a single umbilical artery on ultrasound is \nSelect and explain. \nA. An Indicator of considerably increased incidence of major malformations in the fetus, B. Occurs in 10% of newborns, C. Insignificant, D. Equally common in newborn of diabetic and nondiabetic mothers', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The presence of a single umbilical artery may be associated with congenital malformations.', 'role': 'assistant'}]