This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Fetus Placenta & Fetal Membrane, Subject name: Gynaecology & Obstetrics
The finding of a single umbilical artery on examination of the umbilical cord after delivery is: 
Select and explain. 
A. Insignificant, B. Occurs in 10% of newborns, C. An indicator of considerably increased incidence of major malformation of the fetus, D. Equally common in newborn of diabetic and nondiabetic mothers
C: An indicator of considerably increased incidence of major malformation of the fetus
Answer: C: An indicator of considerably increased incidence of major malformation of the fetus 
Explanation: Ans. is c, i.e. An indicator of considerably increased incidence of major malformation of the fetusRef: Williams Obs 23/e, p 582Single Umblical ArteryIt is seen in 07-0.8% cases of single pregnancy and 5% of twin pregnancyMore common in diabetic patients and black patients.Finding of a single umbilical artery is not insignificant and is associated with:i. Congenital malformations of the fetus in 20-25% cases amongst which cardiovascular and genitourinary anomalies are common.ii. Increased chances of abortion, prematurity, IUGR and perinatal mortality.