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: Dental
Which of the following stains is used to study fungal morphology in tissue sections – 
Select and explain. 
A. PAS, B. Von–kossa, C. Alzarin–red, D. Masson's Trichrome
A: PAS
Answer: A: PAS 
Explanation: "The periodic acid schiff (PAS) and methenamine silver stains are valuable methods for the demonstration of fungal elements in tissue sections."