Answer- D. It stops metabolic and enzymatic activity of the cellTt is a type ofAcidic dye stains the basic components of cell & basic dye stains the acidic components of cell.Leishman's stain contains eosin & methylene blue in acetone free methyl alcohol.Methyl alcohol acts as a fixative.Acetone if present, will destroy the cell membraneMethylene blue ("polychromed"), the basic dye and eosin, the acidic dye exists as thiazine eosinate, which dissociates into the component dyes, when diluted with distilled water.Methyl blue stains the nucleus & basophilic granules of WBC, whereas eosin stains the eosinophilic granules.It is generally used to differentiate & identily leucocytes, malaria parasites & trypanosomas