This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Radiology
[{'content': 'Egg shell calcification seen in silicosis is due to \nSelect and explain. \nA. Hilar lymphnode enlargement, B. Pleural thickening, C. Pulmonary edema, D. Dilated vessels', 'role': 'user'}, {'content': 'Answer: A \nExplanation: (a) Hilar lymphnode enlargement > Enlargement of the hilum is common with chronic and accelerated silicosis. In about 5-10% of cases, the nodes will calcify circumferentially, producingso-called "Eggshell" calcification.> This finding is not pathognomonic (diagnostic) of silicosis. In some cases, the pulmonary nodules may also become calcified.', 'role': 'assistant'}]