This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory system, Subject name: Pathology
[{'content': 'Anthracosis is due to inhalation of- \nSelect and explain. \nA. Coal dust, B. Asbestos dust, C. Silica dust, D. Berylium dust', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ref:Textbook of pathology (Harsh mohan)6th edition, page no. 488 Anthracosis is not a lung disease in true sense but is the common, benign and asymptomatic accumulation of carbon dust in the lungs of most urban dwellers due to atmospheric pollution and cigarette smoke (anthacite refers to coal). Anthracotic pigment is deposited in the macrophages in the alveoli and around the respiratory bronchioles and into the draining lymph nodes but does not produce any respiratory difficulty or radiologic changes', 'role': 'assistant'}]