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
Which of the following represents the additional component in pentology of Fallot? 
Select and explain. 
A. Atrial Septal Defect (ASD), B. Ventricular Septal Defect (VSD), C. Right ventricular Hyperophy (RVH), D. Pulmonic Stenosis
A: Atrial Septal Defect (ASD)
Answer: A: Atrial Septal Defect (ASD) 
Explanation: Pentology of fallot is a rare anomaly which consist of all structural anomalies of tetralogy of fallot together with an ostium secondum ASD. Ref: Essential pediatrics by O.P.Ghai 6th edn/page 406; An Introduction to Electro Cardiography, 7th Edition By Leoschamroth page267.