Why Are Public Water Supplies Monitored for Fecal Coliform Bacteria

Multiple Choice

Why are public water supplies monitored for fecal coliform bacteria despite the fact that most strains of E.coli do not cause disease

A) E.coli is the best indicator of sewage-contaminated water because it doesn't appear in the environment except from human and animal feces.
B) The fecal coliform test is the least expensive,though not most accurate,way to test for sewage contamination.
C) Contrary to what is generally accepted,E.coli is in fact a deadly disease causing pathogen.
D) E.coli is the only bacteria in our water supply that we know how to test for.