Question

Match column I with column II and select the correct option.

• A. 1 - P, 2 - Q, 3 - R
• B. 1 - R, 2 - Q, 3 - P
• C. 1 - Q, 2 - R, 3 - P
• D. 1 - Q, 2 - P, 3 - R

Answer 1

The correct option is C 1 - Q, 2 - R, 3 - P

The industries which are the source of water pollution include chemical and metallurgical industries, food processing plants, textiles, petroleum, paper manufacturing etc.

Industrial waste water contains toxic heavy metals like mercury, cadmium, copper, lead etc. Elements with density > 5 g/cm3 are called heavy metals.

Eichhornia crassipes (water hyacinth) is an aquatic weed commonly called the 'Terror of Bengal'. It is an invasive species that competes strongly with the native species in the aquatic environment. It effectively utilizes the aquatic nutrients and solar energy. It spreads on the surface of water and cuts out the light and it also causes an increase in the oxygen demand, which hampers aquatic life.

Indicator organisms are utilized to evaluate the presence of pollutants in that environment. Escherichia coli (E. coli) in water bodies is an indicator of the presence of faecal material in the water bodies.