<prompt> What is the staining technique used hereGrams stainMethylene blue stainAlbe s stainAcid fast stain  <response>: Acid-fast Pink bacilli in the blue background; M.tuberculosis Most isolates of Mycobacterium, Nocardia, and Rhodococcus species are acid-fast. Acid-fast bacteria are those that retain carbolfuchsin basic fuchsin dissolved in a phenol-alcohol-water mixture even when decolourized with hydrochloric acid in alcohol due to mycolic acid in cell wall Ref : Ananthanarayana textbook of Microbiology 9th edition Pgno : 13-14 