<prompt> Enterobacteriacae is classfied based on-Mannitol fermentationCatalase and oxidase reactionOxygen requirmentLactose fermentation  <response>: Ans. is d i.e., Lactose fermentation o Initially Enterobacteriacea was classifed on the bases of their lactose fermenting ability on MacConkeys medium, the most popular medium for the isolation of fecal bacilli.o Lactose fermenters produce pinkbright red colonies on MacConkeys agar , while lactose non-fermenters produce pale colonies :Lactose fermenters rapid : These are Coliforms, e.g. Escherichia. Klebsiella and Enterobacter aerogenes.Late lactose fermenters slow : These are Shigella Sonnei, Serratia, Citrobacter, Arizona, Providencia and Ervinia.Non-lactose fermenters : Shigella except Shigella Sonnei, Salmonella, Proteus. 