This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Medicine
A continuous murmur is heard in all of the following conditions except 
Select and explain. 
A. Ventricular septal defect with aoic regurgitation, B. Patent ductus aeriosus, C. Coronary aeriovenous fistula, D. Venous hum
A: Ventricular septal defect with aoic regurgitation
Answer: A: Ventricular septal defect with aoic regurgitation 
Explanation: A continuous murmur is predicated on a pressure gradient that persists between two cardiac chambers or blood vessels across systole and diastole. The murmurs typically begin in systole, envelop the second hea sound (S2 ), and continue through some poion of diastole.They can often be difficult to distinguish from individual systolic and diastolic murmurs in patients with mixed valvular hea disease.The classic example of a continuous murmur is that associated with a PDA, which usually is heard in the second or thirdinterspace at a slight distance from the sternal border. Other causes of a continuous murmur include a ruptured sinus of Valsalva aneurysm with the creation of an aoic-right atrial or right ventricular fistula, a coronary or great vessel aeriovenous fistula, and an aeriovenous fistula constructed to provide dialysis accessRef: Harrison's 18/e p1829