DDT cannot be broken down or converted to harmless state by natural processes of oxidation or biological decomposition. Hence it is non biodegradable.

Correct Option: A

DDT cannot be broken down or converted to harmless state by natural processes of oxidation or biological decomposition. Hence it is non biodegradable.

Hydrilla is a fresh water plant.

Correct Option: A

Hydrilla is a fresh water plant.

E. coli lives in the human intestine. If they are present in water it indicates that the water is polluted. E.coli coliform count test is done.

Correct Option: A

E. coli lives in the human intestine. If they are present in water it indicates that the water is polluted. E.coli coliform count test is done.

E. coli grows in water polluted by sewage and domestic waste.

Correct Option: C

E. coli grows in water polluted by sewage and domestic waste.

High concentration of DDT disturbs calcium metabolism in birds which caused thinning of eggshell and their premature breaking.

Correct Option: D

High concentration of DDT disturbs calcium metabolism in birds which caused thinning of eggshell and their premature breaking.