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: Pathology
[{'content': 'Which of the following is a stain for hea failure cells?- \nSelect and explain. \nA. PAS, B. Prussian blue, C. Sudan black, D. Oil red', 'role': 'user'}, {'content': "Answer: B \nExplanation: Hea failure cells: Hemosiderin-laden macrophages Found in lung affected by CVC lung and not in the hea. Hemosiderin pigment in these cells stains blue with Prussian blue stain (Perl's stain).", 'role': 'assistant'}]