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: Pathology
[{'content': 'True About ostium premium ASD \nSelect and explain. \nA. Results in right axis detion(RAD) on the ECG, B. Is seen in Holt-Oram syndrome, C. Less common form than secundum ASD, D. May be left to close spontaneously', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ostium secondum defects are the most common type of ASD, and they are seen in Holt-Oram syndrome.', 'role': 'assistant'}]