Culture media used for corynebacterium diphtheria is:

Ans. C: Loeffler's serum slope Corynebacterium diphtheria/Klebs-Leiffler bacillus It is a facultatively anaerobic Gram positive organism, characterized by non-encapsulated, non-sporulated, immobile, straight or curved rods with a length of 1 to 8 pm and width of 0.3 to 0.8 Jim, which form ramified aggregations in culture (looking like "Chinese characters"). The bacterium may contain polymetaphosphate aggregates called Volutin granules. In order to accurately identify C. diphtheriae, a Gram stain is performed to show gram-positive, highly pleomorphic organisms with no paicular arrangement (classically resembling Chinese characters). Then, culture the organism on an enrichment medium, namely ',Offler's serum. After that, use a selective plate known as tellurite agar which allows all Corynebacteria (including C. diphtheriae) to reduce tellurite to metallic tellurium producing brown colonies and, only in the case of C. diphtheriae, a black halo around the colonies allowing for easy differentation of the organism.