Which dye is described as staining collagen yellow in the image?

• A. Safran
• B. Eosin
• C. Hematoxylin
• D. Orcein

Answer: (A)

Collagen appears yellow because safran (saffron) is used in certain trichrome staining methods to color collagen yellow, creating clear contrast with other tissue components. This selective staining helps distinguish the connective tissue framework from muscle or cytoplasm, which are colored differently by the other reagents in the stain sequence. Eosin would give pink/red hues to cytoplasm and matrix, hematoxylin stains nuclei blue, and orcein highlights elastic fibers rather than collagen, so they wouldn’t produce the yellow collagen seen here.