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: Skin
[{'content': "Which of the following stains is used to study fungal morphology in tissue sections \nSelect and explain. \nA. PAS, B. Von- kossa, C. Alizarin Red, D. Masson's Trichrome", 'role': 'user'}, {'content': "Answer: A \nExplanation: A i.e PAS The periodic Acid Schiff (PAS) stain is a valuable method for the demonstration of fungal elements in tissues. Von Kossa stain and Alizarin Red are used to identify calcium, while Masson's Trichrome is used to identify collagen, muscle and fibrin.", 'role': 'assistant'}]