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': "Ebstein's anomaly is seen with intake of – \nSelect and explain. \nA. Mercury, B. Copper, C. Lithium, D. Lead", 'role': 'user'}, {'content': "Answer: C \nExplanation: Teratogenic cardiovascular defects of lithium →\xa0Ebstein's anomaly, Tricuspid atresia\n\nEtiology of CHD\n\nThe etiology of the majority of CHDs is not known.\nIn less than 10% of cases, the cause and effect relationship has been established.\nBoth environmental and hereditary factors play a role in the etiology of CHDs.\n\n1. Hereditary factors\n\n\xa0A higher incidence of CHD in siblings suggests heredity as an important factor.\nThe strongest familial tendency is known in AST associated with bony abnormalities (Holt oram syndrome)\nOther hereditary conditions have been mentioned in subsequent explanations.\n\n2. Environmental factors\n\nThose who have an inherited tendency, develop CHD due to unfavourable environmental factors\nOf these the most well known is high altitude → There is a higher incidence of PDA and ASD in children born at a high altitude.\nOther important environmental factors are : -", 'role': 'assistant'}]