Which statement is true for Masson's Trichrome technique?

• A. Acid Fuchsin initially stains the collagen red
• B. Aniline Blue initially stains the collagen red
• C. Hematoxylin initially stains the collagen red
• D. Erythrosine initially stains the collagen red

Answer: (A)

Masson's Trichrome differentiates tissue components by color using three dyes, so you can distinguish collagen from muscle and nuclei on a single slide. In the classic protocol, nuclei stain dark blue or black with hematoxylin, muscle and cytoplasm take a red color from acid fuchsin, and collagen is colored blue (often with aniline blue; some variants may use a green counterstain). Because of this, collagen is blue, not red, in Masson's Trichrome. Erythrosine isn’t part of the standard sequence. The practical takeaway is that muscle appears red, collagen appears blue, and nuclei appear dark.