School of fish appearance is characteristic of -
Ans. is 'c' i.e., Haemophillus ducreyi* H duceryi is Gram negative but often may appear Gram positive and frequently shows bipolar staining.* The bacilli may be arranged in small groups or whorls or in parallel chains giving a "school offish" or "rail road track appearance".
Bordetella pertussis
Yersinia enterocolitica
Haemophillus ducreyi
Legionella
Bacteria