This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bacteria, Subject name: Microbiology
Culture medium used for corynebacterium diphtheriae- 
Select and explain. 
A. Loefflers serum slope, B. Tetrathionate broth, C. Selenite 'F' broth, D. Chocolate agar
A: Loefflers serum slope
Answer: A: Loefflers serum slope 
Explanation: Ans. is 'a' i.e., Loeffler's serum slope * The usual media employed for cultivation of diphtheria bacillus are1) Loeffler's serum slope# It is used for rapid diagnosis as growth is shown within 4-8 hours.2) Tellurite blood agar (Tinsdale medium)# It acts as selective media, as tellurite inhibits growth of most other bacteria.# Growth may take two days to appear.