Answer:
Option 5, Peracetic acid
Explanation:
Options
Solution
Peracetic acid is used as a cleanser and disinfectant in food industry and not in water and wastewater treatment plants.
Chlorine is one of the commonly used disinfectants across the globe and one of the benefits of chlorine is that it also has residual disinfectant properties. UV however stronger than chlorine as disinfectant does not have residual disinfectant properties. Copper sulphate is a disinfectant used to kill fungi and algae and ozone is used to kill bacteria and viruses.
Hence, option 5 is correct
