Which description best represents Mayer's mucicarmine staining results for mucin, Cryptococcus neoformans capsule, nuclei, and background?

• A. Mucin, capsule of Cryptococcus neoformans = deep rose to red; nuclei = black; background blue or yellow
• B. Mucin only; capsule blue; nuclei red; background blue
• C. Nuclei blue; mucin green; background brown
• D. No mucin staining observed

Answer: (A)

Mayer's mucicarmine highlights acidic mucins and the polysaccharide capsule of Cryptococcus neoformans in a distinct rose-red color, while the nuclei are counterstained dark (blue-black) and the background takes a blue (sometimes yellow) hue. This pattern—mucin and cryptococcal capsule staining deep rose to red, nuclei stained black, and background blue or yellow—directly matches the described result. The other patterns would not show both mucin and the cryptococcal capsule in red or would miscolor the nuclei or background.