The purification process for fresh water is done by

• A. Distillation
• B. Boiling only
• C. Chlorination only
• D. Sedimentation and filtration

Answer: (D)

Removing solid particles through settling and filtering is the essential initial purification step. Water is allowed to sit in settling basins so heavier particles drop out (sedimentation), then it's passed through filters to trap remaining suspended solids and improve clarity. This physical cleanup reduces turbidity and prepares the water for disinfection, making it safer for consumption. Distillation, though effective, is energy-intensive and not practical for municipal supply. Boiling only sterilizes but doesn’t remove dissolved contaminants. Chlorination alone disinfects but doesn’t remove particulates or dissolved substances. So, sedimentation and filtration form the core purification stage.