Question

Which one of the following is a fresh water indicator organism?

• A. Tubifex
• B. Daphnia
• C. Sludge worm
• D. All of the above

Answer 1

The correct option is B Daphnia

Water pollution is the major cause of several chronic diseases. The potable water must be treated to get rid of certain harmful microorganism. Daphnia, trout fishes, and larvae of stoneflies are the example of freshwater indicator and tubifex, E. Coli, sewage fungus, sludge worms, blood worms are the indicator of polluted water.

So, the correct answer is option B.