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: Medicine
Commonest type of congenital cyanotic heart disease: 
Select and explain. 
A. Atrial septal defect, B. Ventricular septal defect, C. Tetralogy of Fallot, D. Patent ductus arteriosus
C: Tetralogy of Fallot
Answer: C: Tetralogy of Fallot 
Explanation: None