<prompt> The best culture medium for primary isolation of H. influenzae is?Chocolate agarFildes agarLevinthals mediumNutrient agar  <response>: Fildes agar is made by adding peptic digest of blood to nutrient agar. It gives copious growth of H. influenzae A.K.A Pfeiffers bacillusand it is the best culture medium for the primary isolation of H. influenzae. The other media used for the isolation of H. influenzae are chocolate agar, blood agar, nutrient agar and Levinthals medium. 