1. What percentage of Earth’s surface is covered by water?
a) 25%
b) 50%
c) 75%
d) 97.5%
Answer: d) 97.5%
2. Which of the following is the largest source of freshwater on Earth?
a) Rivers
b) Lakes
c) Groundwater
d) Glaciers and ice caps
Answer: d) Glaciers and ice caps
3. What is the primary process by which seawater is converted into freshwater?
a) Desalination
b) Filtration
c) Distillation
d) Aeration
Answer: a) Desalination
4. The majority of the world’s population relies on which source for their drinking water?
a) Rivers
b) Lakes
c) Groundwater
d) Reservoirs
Answer: c) Groundwater
5. Which river is the longest in the world?
a) Amazon
b) Nile
c) Yangtze
d) Mississippi
Answer: b) Nile
6. What is the largest saltwater lake in the world?
a) Caspian Sea
b) Great Salt Lake
c) Lake Baikal
d) Dead Sea
Answer: a) Caspian Sea
7. Which of the following is a major factor affecting water scarcity?
a) Overabundance of water
b) Climate change
c) Rapid population decline
d) Excessive rainfall
Answer: b) Climate change
8. What is the main cause of groundwater contamination?
a) Natural mineral deposits
b) Agricultural runoff
c) Volcanic activity
d) Solar radiation
Answer: b) Agricultural runoff
9. What is the purpose of constructing a dam?
a) To prevent floods
b) To generate hydroelectric power
c) To store water for irrigation
d) All of the above
Answer: d) All of the above
10. Which of the following is a renewable source of water?
a) Fossil aquifers
b) Desalinated seawater
c) Rainwater harvesting
d) Acid rain
Answer: c) Rainwater harvesting
11. What is the term for the process by which water vapor turns into liquid water?
a) Condensation
b) Evaporation
c) Precipitation
d) Transpiration
Answer: a) Condensation
12. Which of the following is a major component of the water cycle?
a) Ocean currents
b) Volcanic eruptions
c) Earth’s magnetic field
d) Carbon dioxide levels
Answer: a) Ocean currents
13. Which type of water source is formed by melting glaciers?
a) Springs
b) Glacial lakes
c) Artesian wells
d) Reservoirs
Answer: b) Glacial lakes
14. What is the primary purpose of a watershed?
a) Agricultural irrigation
b) Urban development
c) Water collection and drainage
d) Air pollution control
Answer: c) Water collection and drainage
15. Which of the following is a natural spring that discharges water at a temperature higher than the human body?
a) Geyser
b) Oasis
c) Fjord
d) Lagoon
Answer: a) Geyser
16. What is the main component of Earth’s atmosphere that combines with water to form precipitation?
a) Nitrogen
b) Oxygen
c) Carbon dioxide
d) Water vapor
Answer: d) Water vapor
17. Which river is known as the “Yellow River” and is often associated with significant sediment discharge?
a) Yangtze
b) Indus
c) Huang He
d) Mekong
Answer: c) Huang He (Yellow River)
18. What is the purpose of a retention pond?
a) Flood prevention
b) Water storage
c) Stormwater management
d) Drinking water supply
Answer: c) Stormwater management
19. What is the process of water movement through a plant and its evaporation from aerial parts called?
a) Transpiration
b) Infiltration
c) Percolation
d) Precipitation
Answer: a) Transpiration
20. Which ocean is the largest and holds the majority of Earth’s saltwater?
a) Atlantic Ocean
b) Indian Ocean
c) Southern Ocean
d) Pacific Ocean
Answer: d) Pacific Ocean