Stain used to stain X chromosome: (A) Quinacrine, (B) Acriflavin Schiff reagent, (C) Methylene blue, (D) Fluorescent green
Answer is B. Barr body is formed due to random inactivation or condensation of one of the 2 female chromosomes in all the somatic cells of female mammals. Buccal smears are known to be potential source of Barr bodies. Acriflavin schiff stain was used in staining these Barr bodies. Ref: NCBI.org