Microbiology A person working in an abattoir presented with pustule on hand which turned into ulcer. Which of the following will best help in diagnosis? A Polychrome methylene blue B Carbol fuchsin C Acid fast stain D Calcofluor white 💡 Explanation A person working in an abattoir presented with pustule on hand which turned into ulcer. Which of the following will best help in diagnosis? ✓ Correct Answer: A. Polychrome methylene blue