Name the group of bacteria found in our intestine, what does the presence of these bacteria in water indicate.

It's from class XIII.

Answer :

escherichia coli is the group of bacteria present in the human intestine.they benefit the host by gleaning the energy from the fermentation of undigested carbohydrates and the absorption of short-chain fatty acids.
 E.coli are used as indicators to measure the degree of pollution and sanitary quality of well water, 
E. coli is the bacteria of genus escherichia which is found in our intestine and there presence in water indicates that water is contaminated .