Which of the following is an example of a point source of pollution?

A point source of pollution is defined as a specific, identifiable location from which pollutants are discharged into the environment. This includes facilities such as factories, sewage treatment plants, or wastewater sources that have a single, concentrated point of discharge.

The choice of sewage treatment plant discharges is correct because these plants release treated wastewater through a specific outlet into a body of water, making it easy to identify the origin of the pollution. The discharge point can often be monitored and regulated, which aligns with the characteristics of point source pollution.

In contrast, agricultural runoff, atmospheric deposition, and lawn runoff are examples of non-point source pollution. Agricultural runoff comes from widespread farming areas and can vary significantly in intensity and contaminants, making it difficult to pinpoint an exact source. Atmospheric deposition refers to pollutants that settle from the atmosphere over larger areas, and lawn runoff can occur from numerous residential properties, contributing to pollution in a more diffuse manner. These non-point sources lack the specific discharge points that characterize point source pollution.