Stage 1: Identify common diarrhoeal pathogens.
The primary bacterial agents responsible for diarrhoea are E. coli (specifically ETEC, EHEC, and EPEC strains), Vibrio cholerae, Shigella, and Salmonella.
Stage 2: Evaluate the provided choices.
- (A) Enterobacter cloacae: This is typically an opportunistic pathogen and infrequently causes diarrhoea.
- (B) Escherichia coli: Strains that are enterotoxigenic and enterohemorrhagic are known to cause diarrhoea. This option is correct.
- (C) Pemphigus vulgaris: This is not a bacterium but an autoimmune condition characterized by blistering.
- (D) Yersinia pestis: This bacterium is the cause of plague and does not typically lead to diarrhoea.
Stage 3: Final determination.
The accurate selection is Escherichia coli.