Waste water is (d) Water coming out of a laundry.
Explanation: Wastewater refers to water that has been used and contains waste products, like from laundry where soap and detergents contaminate the water.
Why other options are incorrect:
(a) Water trickling from a damaged tap:
This is simply water that has been lost due to a leak, not considered wastewater.
(b) Water coming out of a shower:
While showering generates wastewater, the term usually refers to the combined wastewater from various household sources, including the laundry.
(c) Water flowing in a river:
This is natural freshwater that has not been used or contaminated by human activities.