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: Social & Preventive Medicine
[{'content': 'All are features of Silico-tuberculosis except \nSelect and explain. \nA. High sputum AFB +ve, B. Children of such cases do not get disease, C. Impairement of total lung, D. Nodular fibrosis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: In recent years doubts have risen in the association between silicois and tuberculosis as:\n\nSputum is rarely AfB+\nChildren and women of sts do not develop tuberculosis\nPost mortem of sts fail to prove existence of tuberculosis\nRadilogical evidence of both conditions is similar.', 'role': 'assistant'}]