This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Valvular hea diseases, Subject name: Medicine
Which among the following is FALSE feature regarding Atrial Septal Defect (ASD) ? 
Select and explain. 
A. Pulmonary plethora leads to pulmonary aery hypeension, B. Murmur presents early in the course of disease, C. Flow murmur is present leading to mid diastolic murmur, D. Shunt murmur is absent
B: Murmur presents early in the course of disease
Answer: B: Murmur presents early in the course of disease 
Explanation: Cardiac disease Murmur ASD Shunt murmur is absent but flow murmur is present leading to mid diastolic murmur. Pulmonary plethora will lead to pulmonary aery hypeension and development of loud P2. Presents late Mitral stenosis Leads to mid diastolic murmur. Later PAH develops and leads to loud P2. HOCM Result in ejection systolic murmur with narrow split/ paradoxical split S2 Hence it is unlikely as a diagnosis in this case Pulmonary aery Hypeension Leads to loud P2. Severe PAH, early Pulmonic regurgitation can occur. Called as Graham Steel murmur.