Point source pollution can be define as the pollution that can be caused by a pollutant whose source of origin is known. As the source of origin is known the path of the pollutant can be traced back to it's origin hence, the pollution can be controlled.
Among the options given, D. Acid from abandoned mines. is the correct option this is because of the fact that the source of origin of the pollutant is known that is abandoned mines.
Point source water pollution refers to contaminants that enter a waterway from a single, identifiable source, such as a pipe or ditch. Examples of sources in this category include discharges from a sewage treatment plant, a factory, or a city storm drain.