Question

Which of the following is called a natural water purifier?
A) Bacteria
B) Algae
C) Protozoa
D) Virus

Answer 1

Water is a transparent, colourless, tasteless, odorless liquid.It is the main constituent of Earth’s hydrosphere.Human beings contain around 70% water in their body.It is essential for the survival of living beings on this Earth.

Complete answer:
Water purifiers:

Water purifiers are the filters that remove impurities by lowering the contamination of the water.
Water purifiers can use fine physical barriers like fine filters, a chemical process or a biological process.
Water purifiers cleanse water to different extents for many purposes like agricultural irrigation, drinking, swimming pools, aquariums, etc.
Water purifiers use the processes such as sieving, adsorption, ion exchange and other processes in order to remove unwanted substances from the water.
Natural water purifier:
Natural water purifiers use biological processes like processes of microorganisms.
These microorganisms feed upon the organic substances that are present in the wastewater and make the water clear and clean.
Protozoans play an important role in water purification.
They are used as natural water purifiers.
Therefore, it has been clear from the above discussion that Protozoa is called a natural water purifier.

Hence, option C is the correct answer for this question.

Note: Before discharging the wastewater into the lakes and rivers, the waste water must be processed or purified in order to remove impurities from it so that it cannot pollute the water of the river or lake.And reduce the water pollution to some extent.