What is the term for water that is safe to drink?
a) Saline water
b) Distilled water
c) Potable water
d) Polluted water
Answer: c) Potable water

Which process is primarily responsible for the formation of clouds?
a) Evaporation
b) Condensation
c) Precipitation
d) Infiltration
Answer: b) Condensation

Which of the following is not a method of water conservation?
a) Drip irrigation
b) Water recycling
c) Over-irrigation
d) Rainwater harvesting
Answer: c) Over-irrigation

What is the main cause of algal blooms in water bodies?
a) Low oxygen levels
b) High nutrient levels
c) Cold temperatures
d) High salinity
Answer: b) High nutrient levels

Which of the following processes is used to remove bacteria from water?
a) Filtration
b) Chlorination
c) Sedimentation
d) Evaporation
Answer: b) Chlorination

Which gas is most commonly produced during the decomposition of organic matter in water?
a) Methane
b) Carbon dioxide
c) Oxygen
d) Nitrogen
Answer: a) Methane

Which of the following is a byproduct of the water treatment process?
a) Sludge
b) Oxygen
c) Nitrogen
d) Hydrogen gas
Answer: a) Sludge

What is the term for the flow of water over the ground surface?
a) Infiltration
b) Runoff
c) Evaporation
d) Percolation
Answer: b) Runoff

Which type of soil has the highest water retention capacity?
a) Sandy soil
b) Loamy soil
c) Clay soil
d) Peaty soil
Answer: c) Clay soil

What is the main cause of water scarcity in arid regions?
a) Overpopulation
b) Deforestation
c) Lack of rainfall
d) Pollution
Answer: c) Lack of rainfall