The meaning communicated by consumer efficiency:
C). using resources without being wasteful.
The word 'efficient' stands for 'the careful or thoughtful usage of resources and maximize its utilization.'
In the given excerpt, the usage of the phrase 'consumer efficiency' also stands for 'careful usage of resources so they do not get wasted in any manner.'
This implies that the consumers must employ techniques that reduce the wastage of water resource and enhances their value.
Thus, option C is the correct answer.
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