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: Pediatrics
[{'content': "Tetralogy of Fallot's present with one of the following – \nSelect and explain. \nA. Cenral cyanosis with clubbing, B. Cardiomegaly, C. Left ventricular hypertrophy, D. Normal ECG and Chest x-ray", 'role': 'user'}, {'content': "Answer: A \nExplanation: Clinical features of TOF :\n\nDyspnea on exertion and exercise intolerance → Most common.\nCyanosis usually presents after the neonatal period\nHypoxemic or cyanotic spells (Tet spells)\nCommonest congenital lesion with which squatting is used\nClubbing\n\nAuscultatory findings :\n\nS1\xa0→\xa0\xa0Normal\nS2\xa0→ \xa0Single predominantly Aortic\nMurmur →\xa0\xa0Ejection systolic\nTOF patients are RARELY CYANOTIC AT BIRTH\n\nChest x-ray\n\nNormal heart size\nOligaemic lung fields\nRight aortic arch present in 25% case\nBOG → Right axis deviation, Inverted Twave, `P' pulmonale\n\nAbout option ‘b’\n\nPulmonary stenosis causes pressure overload → Concentric right ventricular hypertrophy without cardiac enlargement.", 'role': 'assistant'}]