This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
[{'content': 'Oil red Or staining is used for \nSelect and explain. \nA. Frozen section, B. Glutaraldehyde fixed specimen, C. Alcohol fixed specimen, D. Formalin fixed specimen', 'role': 'user'}, {'content': 'Answer: A \nExplanation: ref Bancroft histology 7/e p83 Fresh cryostat sections must be used for oil red o stain', 'role': 'assistant'}]