Which term describes pollution from many diffuse sources rather than from a single source?

• A. Nonpoint Source
• B. Point Source
• C. Secondary Source
• D. Ambient Source

Answer: (A)

Pollution from many diffuse sources is described as nonpoint source pollution. This occurs when contaminants enter water from broad areas rather than a single outlet, often carried by rain or snowmelt across fields, streets, and disturbed lands. Because it comes from numerous small inputs—fertilizers and pesticides washing off agricultural land, oil and debris from roads, sediment from construction sites—the pollution is spread over a large area and is harder to trace and control. Mitigation focuses on watershed-wide practices, like better land management, runoff control, and reducing impervious surfaces, rather than shutting down one discharge point. A single identifiable discharge would be a point source, while secondary or ambient source terms don’t describe this diffuse, landscape-wide pattern.