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
Which of the following is a stain for hea failure cells?- 
Select and explain. 
A. PAS, B. Prussian blue, C. Sudan black, D. Oil red
B: Prussian blue
Answer: B: Prussian blue 
Explanation: 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).