Best carmine method is used to demonstrate which type of biological molecule?

• A. Carbohydrates
• B. Proteins
• C. Lipids
• D. Nucleic acids

Answer: (A)

The key idea is that Best's carmine staining is specific for carbohydrate-rich substances, especially glycogen. Carmine has an affinity for polysaccharides, so when tissue sections containing glycogen are stained with this method, the glycogen appears prominently (often as a distinct red color). That makes it the best choice for demonstrating carbohydrates. Proteins, lipids, and nucleic acids are revealed best with other stains or techniques (proteins by different protein-reactive dyes, lipids by Sudan dyes, nucleic acids by Feulgen or other DNA stains), so Best's carmine stands out specifically for identifying carbohydrate-containing structures like glycogen.