Question

Suspended impurities in water are removed before the water is supplied to homes by:

• A. sedimentation
• B. filtration
• C. treating with alum
• D. all of these

Answer 1

The correct option is D

all of these

Explanation for correct answer -

• Sedimentation - the process of setting down of suspended and undissolved impurities present in water. this process can be accelerated by treating water with alum.
• Filtration - it removes the remaining suspended impurities after sedimentation by passing water through a filter made of gravel and fine sand.
• Treating with alum - alum precipitates out the suspended impurities and make water clear.

therefore, option D is correct.