Final answer:
Bleaching powder is used to make water germ-free by disinfecting it and killing harmful organisms such as bacteria, making it safe for human use.
Step-by-step explanation:
Bleaching powder, which typically refers to a dilute solution of sodium hypochlorite, is used in water treatment processes. The primary role of bleaching powder is as a disinfectant. It is added to water to kill bacteria and other harmful organisms. This makes the water safe for human use by removing biological contaminants. Chlorine is the most common compound used for this purpose, and while it helps in the disinfection process, the amount has to be carefully controlled. Excessive amounts of disinfectants can be harmful to humans, whereas too little will not effectively eliminate the harmful bacteria and pathogens.
Appropriate Use of Bleaching Powder
Disinfection of swimming pools to control bacteria, viruses, and algae
Industrial processes, such as bleaching wood pulp
Household cleaning and laundry for removing stains and keeping whites whiter
The correct answer to the question about the use of bleaching powder is therefore B. To make water germ-free.