What color does this lipid-staining method assign to lipids?

• A. Red
• B. Blue
• C. Green
• D. Yellow

Answer: (A)

Fat-soluble lipid stains work by dissolving into the lipid droplets inside cells. They have a strong affinity for neutral lipids like triglycerides and cholesterol esters, so they partition into those lipids and give a vivid red color under the microscope. This red signal is what identifies lipid-rich areas, especially in frozen sections stained with a lipid-specific dye. Other colors don’t reflect how this staining method interacts with lipids, so red is the expected result.