Which of the following is the most likely way for bacteria and viruses to enter a water supply? A) Increased photosynthesis releases bacteria and viruses. B) Poor sanitation habits cause water to mix with sewage. C) Water from a burst dam sweeps particulate matter into a nearby river. D) Chemical fertilizers dumped into the water attract bacteria and viruses
Answer - B Lack of proper sanitation facilities and water drainage system can cause merging of fresh water with the sewage and allow bacteria, viruses and various other microbes to enter the water supply. This causes infectious diseases.
