This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Gestational Diabetes Mellitus, Subject name: Gynaecology & Obstetrics
One of the following is the most specific cardiac anomaly of a newborn to a diabetic mother: 
Select and explain. 
A. VSD, B. Transposition of great vessels, C. PDA, D. Pulmonic stenoisis
B: Transposition of great vessels
Answer: B: Transposition of great vessels 
Explanation: Congenital malformation in fetus of a diabetic mother : * M/C system involved in congenital malformation CVS > CNS * Most specific structural anomaly seen - caudal regression syndrome ( sacral agenesis ) * Most specific cardiac anomaly seen in babes of diabetic mother - TGV