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': "Pulmonary flow is decreased in - \nSelect and explain. \nA. Fallot's tetralogy, B. Ebstein'sanomally, C. Common atria, D. TG V with intact septum", 'role': 'user'}, {'content': 'Answer: A \nExplanation: Rapid breathing in response to low oxygen levels and reduced pulmonary blood flow can occur. The hea murmur, which is commonly loud and harsh, is often absent in the first few days of life. The aerial oxygen saturation of babies with tetralogy of Fallot can suddenly drop markedly Ref Davidson 23rd edition pg 455', 'role': 'assistant'}]