This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
[{'content': '‘Himalayan P waves’ in ECG is characteristic of: \nSelect and explain. \nA. Atrial septal defect, B. Eisenmenger syndrome, C. Tetralogy of Fallot, D. Ebstein’s anomaly', 'role': 'user'}, {'content': 'Answer: D \nExplanation: 12 – lead ECG\n\nRarely normal\nAbnormal P waves consistent with right atrial enlargement – ‘Himalaya P waves”.\nRBBB in 75-92%\nPR prolongation is common due to RA enlargment\nVentricular pre-excitation 10-30%', 'role': 'assistant'}]