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: Pathology
[{'content': 'Special stain for Amyloid which is most diagnostic - \nSelect and explain. \nA. Lugol’s Iodine, B. Sudan black, C. Congo red polarized light, D. Congo red in Illumination', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Congo red is not used in lipid staining. It is used in the staining of amyloid protein.', 'role': 'assistant'}]