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: Pediatrics
The following features are true for tetralogy of Fallot, EXCEPT: 
Select and explain. 
A. Ventricular septal defect, B. Right ventricular hyperophy, C. Atrial septal defect, D. Pulmonary stenosis
C: Atrial septal defect
Answer: C: Atrial septal defect 
Explanation: The four constituents of Tetralogy of Fallot are ventricular septal defect, pulmonic stenosis, overriding of aoa and right ventricular hyperophy. ADS is not a component of TOF. Ref: Essential Pediatrics, 6th Edition By O P Ghai, Pages 406-8.