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': 'Which of the following stains can be used to demonstrate fat? \nSelect and explain. \nA. Oil red, B. Sudan black B, C. Osmium tetroxide, D. All of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Fat / Lipid can be demonstrated by oil red O, Sudan black B or sudan IV,\xa0Osmium tetroxide.', 'role': 'assistant'}]