Which staining technique uses light green to stain collagen?

• A. Masson's Trichrome
• B. Gomori Aldehyde Fuchsin
• C. Gordon and Sweets
• D. Verhoeff's Van Gieson

Answer: (A)

Masson's Trichrome is a three-dye connective tissue stain that differentiates tissue types by color. In this protocol, collagen takes up the green (light green) dye, while muscle and cytoplasm stain red and nuclei appear dark. This color scheme makes collagen fibers stand out clearly against other tissue components, which is especially helpful for assessing fibrosis and extracellular matrix distribution. Other stains focus on different targets (elastic fibers or different color balances), so they don’t use light green for collagen in the same conventional way.