Which element is important in a water conservation plan?
Correct answer: A. A useful water conservation plan begins with measurement: people need to know how much water is being used, where it is used, and where losses occur. This information helps identify unnecessary consumption. The plan can then include repairing leaks, fitting efficient taps or irrigation systems, scheduling use carefully, collecting rainwater where suitable, and reusing water when it is safe and appropriate. B is wrong because keeping taps open continuously causes direct wastage. C is wrong because unnoticed leaks can waste a large amount of water over time. D is wrong because untreated used water may pollute rivers, ponds, groundwater, and soil. A plan should combine monitoring with practical action rather than relying only on good intentions. Measurement also helps check whether the conservation measures are working. Memory cue: measure, repair, reduce, and reuse safely.