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': 'Amyloid deposits stain positively with all of the following except \nSelect and explain. \nA. Congo Red, B. Crystal violet, C. Methenamine silver, D. Thioflavin ?', 'role': 'user'}, {'content': 'Answer: C \nExplanation: . Methenamine silver', 'role': 'assistant'}]