This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Medicine
The most common location of ventricular septal defect is- 
Select and explain. 
A. Perimembranous, B. Muscular, C. Doubly-committed subaenal, D. None
A: Perimembranous
Answer: A: Perimembranous 
Explanation: The VSD is usually single and situated in the membranous or midmuscular poion of the septum. ( Harrison&;s principle of internal medicine,18th edition,pg no. 1923)