Final answer:
Melanin present in tissue can be bleached using potassium permanganate, a compound known for its strong oxidizing properties that react with natural pigments to decolorize them.
Step-by-step explanation:
Melanin present in tissue can be bleached with the use of various substances. The best choice among the options provided for bleaching melanin in tissues is potassium permanganate (KMnO₄). Potassium permanganate is known for its strong oxidizing properties, which are utilized in treating several skin conditions and in the medical field for disinfection purposes. This compound reacts with natural pigments and converts them into colorless compounds. While iodine and iodophors like povidone-iodine have antiseptic properties due to their oxidizing action, they are less likely to be used as bleaching agents for melanin in tissue.