Which of the following is the most wasteful use of water? a)taking a shower rather than a bath b)watering the garden with recycled water c)running dishwashers before they are completely full d)replacing high-flow showerheads with low-flow showerheads

I think the answer to this is C.

A) Yes it is good to take bath rather than showers but there is no way you could waste water in the shower.

B) Watering the garden is different from showers and the other choices but it all depends on how much you use the water in the garden and if you use recycled water it could bring more good land and water. So we have to eliminate that choice. 

C) Running dishwashers uses a lot of water and if you are running the dishwasher before they are completely full that means you are wasting good water. 

D) If you replace shower-heads with low-flow that means you are saving water as appose to high-flow shower-heads which means you could be wasting water because it is using more water than the low-flow shower-heads.

So C should be the answer
Hope this helped :)
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