The devices which are installed for drawing water from the sources are called______________?

1) climatic conditions
2) quality of water
3) distribution pressure
The correct answer is?
A. only (1)
B. both (1) and (2)
C. both (1) and (3)
D. all (1), (2) and (3)

A. to increase the filtration slow sand filters capacity of
B. to increase the filtration rapid sand filters capacity of
C. for isolated buildings like pools, hotels etc swimming
D. all of the above

A. reducing the excessive flow in sewers
B. disposing of sludge
C. increasing the capacity of storage re-servoirs
D. increasing flow of sewage through imhoff tanks