All of the following stains are used for fat except?: (A) Oil red O, (B) Congo reds, (C) Sudan black, (D) Osmium tetroxide
Answer is B. Ans. is 'b' i.e., Congo red * Congo red is not used in lipid staining. It is used in the staining of amyloid protein.* Stain used for lipids (fatty acids)are Oil red O, Osmium tetroxide, sudan black and sudan III & IV.