Which of the following can be considered an industrial source of wastewater?

Cooling water from plants is considered an industrial source of wastewater because it is a byproduct of operations in industrial facilities, such as power plants or manufacturing plants. These facilities often use water for cooling purposes, which becomes thermally polluted once it's discharged back into the environment. This type of wastewater can contain various pollutants, including metals and chemicals, depending on the industrial process, making it important to treat it properly before being released into water bodies to avoid environmental harm.

The other options represent different types of water sources. Stormwater runoff refers to rainwater that flows over surfaces, collecting pollutants along the way, and is not directly generated from industrial processes. Household sewage comprises wastewater from residential sources, like toilets and sinks, rather than from industrial activities. Groundwater, which is water located beneath the earth’s surface, is a natural resource and does not originate from human activity as wastewater does. Thus, cooling water from plants stands out as a proper example of industrial wastewater.