Sanitary sewage is composed of which of the following?

Sanitary sewage is a complex mixture that originates primarily from domestic sources, including wastewater generated from household activities like bathing, cooking, cleaning, and toilet use, which together is referred to as domestic sewage. However, it also frequently contains industrial waste, particularly where industrial facilities are connected to municipal sewage systems. This combination of domestic and industrial discharges can vary widely in composition but is categorized as sanitary sewage due to its treatment under public health standards.

The inclusion of industrial waste is significant because industrial processes may introduce various chemicals, heavy metals, and other pollutants that are necessary to manage to ensure safe treatment and discharge into the environment. Understanding this mixture is crucial for effectively managing and treating waste, making option C the most accurate answer in recognizing the breadth of what constitutes sanitary sewage.

Other options, such as limiting the composition to only human waste or domestic sewage alone, do not encompass the full scope of sanitary sewage as it exists in real-world settings. Groundwater infiltration, while it may affect the volume of water in sewage systems, does not contribute to the actual composition of sanitary sewage itself. Therefore, option C correctly identifies the components of sanitary sewage as including both domestic and industrial sources.