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
[{'content': 'Clinical features of ostium secondum type of atrial septal defect are all except - \nSelect and explain. \nA. Occurence of congestive failure in childhood, B. Atrial arrhythmias, C. Wide and fixed splitting of the second hea sound, D. Mid-diastolic rumble along the left sternal border', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The foramen secundum, or ostium secundum is a foramen in the septum primum, a precursor to the interatrial septum of the human hea. It is not the same as the foramen ovale, which is an opening in the septum secundum. Infants and children with paial atrioventricular (AV) septal defects and significant mitral regurgitation have poor development and are tachypneic and tachycardic at rest. A hyperinflated thorax, bulging precordium, and Harrison grooves wide split, arrhythmias are often present Ref Davidson 23rd edition pg 450', 'role': 'assistant'}]