The technique shown in the image uses which staining method?

• A. Methenamine silver
• B. Hematoxylin and eosin
• C. Masson's trichrome
• D. PAS

Answer: (A)

Silver-impregnation stains highlight carbohydrate-rich walls by depositing metallic silver, making the targeted structures stand out very dark against a lighter background. The methenamine silver method uses methenamine to drive this silver deposition on fungal cell walls (and can also reveal reticular fibers), so fungal filaments or yeast walls appear black and clearly delineated. This high-contrast, dark staining is distinctive for fungi and is not produced by the other stains listed—H&E gives pink and blue hues, PAS colors polysaccharides magenta, and Masson's trichrome highlights connective tissue in blue/green. The dark, threadlike elements shown align with what methenamine silver stains reveal in tissue.