The problem in the image could be prevented by?

• A. Differentiating the eosin better in the lower dehydrating alcohols
• B. Increasing the staining time
• C. Using stronger eosin
• D. Using different fixative

Answer: (A)

Focus on how the counterstain is tuned. Eosin binds to cytoplasmic components, but if it’s not properly differentiated after staining, the tissue can appear overly pink with poor contrast. Differentiating eosin in the lower dehydrating alcohols uses a mild solvent step that removes loosely bound eosin while preserving the eosin that is truly retained by tissue. This short, controlled wash sharpens cytoplasmic staining and prevents the overstained appearance you’d get if differentiation were skipped or done with stronger conditions. Using a stronger eosin or simply increasing staining time would push the stain toward overcoloration, while changing the fixative wouldn’t specifically correct the excess eosin on the tissue.