Indication of Fecal contamination of water is due to presence of-

Ans. is `a' i.e., E. coli; 'b' i.e., Coliform; sc' i.e., Enterococci Bacteriological indicators of water contamination o Presence of following organism indicate fecal contamination of water. 1) Confirm : by all practical point of view it is assumed that all coliform are fecal in origin unless a non-fecal origin can be proved. 2) Fecal streptococci or enterococci : They regularly occur in feces. Finding offecal streptococci in water is regarded as impoant confirmatory evidence of recent fecal contamination water. 3) Clostridium perfringens : They also regularly occur in feces. Presence of spore of Cl. perfringens and absence of col i form group indicate remote contamination of water.