Question

The microbial quality of treated piped water supplies is monitored by

• A. Identification of all pathognes
• B. Coliform MPN test
• C. Plate count of heterotrophic bacteria
• D. Microscopic examination

Answer 1

The correct option is B Coliform MPN test

MPN (Most Probable Number) index is measure of coliform bacteria.
Pathogenic bacteria are tested and counted in laboratory with great difficulty. Hence, coliform bacteria are tested and counted which themselves are harmless aerobic lactose fermenters but their presence or absence indicates the presence or absence of pathogenic bacteria.