Q. Which of the following is a waterborne disease? Typhoid Cholera Diarrhoea All of the above Answer: All of the above

Q. What is the health effects of excess fluoride in drinking water? Fluorosis Toothaches Lung disease Intestinal infection Answer: Fluorosis.

Q. Which of the following techniques is used to remove fluorides from the water bodies? Osmosis Ion exchange Lime softening Both 2 and 3 Answer: Both 2 and 3

Q. Which of the following is mainly responsible for the causes of water pollution? Afforestation Oil refineries Paper factories Both 2 and 3 Answer: Both 2 and 3

Q. Chlorofluorocarbon are nonflammable chemicals mainly used in _________. Perfumes Refrigerators Air conditioners All of the above Answer: All of the above.

Q. Which of the following salts is the main cause of permanent hardness of water? Magnesium sulphate Magnesium bicarbonate Magnesium carbonate None of the above Answer: Magnesium sulphate.

Q. Which of the following techniques is used for reducing the total dissolved solids (TDS) in the water? Osmosis Ion exchange Distillation Both 2 and 3 Answer: Both 2 and 3.

Q. Which of the following statements are true about CNG -Compressed natural gas? It is a clean fuel It is a harmful fuel It is a polluting fuel All of the above Answer: It is a clean fuel.

Q. Which of the following rivers is called the world’s most polluted river? Ganga River Chenab River Cauvery River Yamuna River Answer: Ganga River.

Q. Which of the following are the primary causes of water pollution? Plants Animals Human activities None of these Answer: Human activities.