This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Microbiology
Best culture for primary isolation of H. influenzae? 
Select and explain. 
A. Blood agar, B. Fildes agar, C. Nutrient broth, D. Tryptose agar
B: Fildes agar
Answer: B: Fildes agar 
Explanation: Ans. is 'b' i.e., Fildes agarH. influenzae does not grow on blood agar.Culture media used for isolation are Fildes agar (best for primary isolation), Levinthal medium (capsulated strains show iridescence) and Chocolate agar.