Which of the following is a common source of wastewater?

Residential areas are a common source of wastewater because they comprise homes where water is used daily for various activities such as cooking, cleaning, bathing, and sanitation. This usage generates a significant amount of wastewater that typically contains human waste, food scraps, and detergents, all of which require treatment before being released back into the environment.

In contrast, public parks primarily produce runoff and stormwater, which does not necessarily qualify as wastewater. Wildlife reserves generally do not contribute to wastewater in the same way that human habitation does, as they are not designed for water consumption or waste generation by people. Vacant lots, while they may collect stormwater, do not usually lead to the generation of wastewater since there are no residential or commercial activities taking place that would produce such discharge. Therefore, residential areas stand out as the primary source of wastewater due to their continual, human-related activities.