The correct answer is A. Bleaching powder.
Bleaching powder is a common household item that is used for a variety of purposes, including sterilizing water. It is a white, crystalline powder that is made by treating calcium chloride with chlorine gas. When dissolved in water, bleaching powder releases chlorine, which is a powerful disinfectant. Chlorine kills bacteria and other microorganisms in water, making it safe to drink.
Alum is a naturally occurring mineral that is used in a variety of applications, including water treatment. It is a white, powdery substance that is soluble in water. Alum can be used to coagulate suspended particles in water, making it clearer. It can also be used to remove bacteria and other microorganisms from water.
Borax is a naturally occurring mineral that is used in a variety of applications, including water
treatment. It is a white, powdery substance that is soluble in water. Borax can be used to soften water and to remove scale from pipes. It can also be used to kill bacteria and other microorganisms in water.Soda powder is a common household item that is used for a variety of purposes, including cleaning and baking. It is a white, powdery substance that is made by treating sodium carbonate with water. Soda powder can be used to disinfect surfaces and to remove stains. It can also be used to make baking soda, which is a common ingredient in baking.
Of the four options, only bleaching powder is extensively used for sterilizing water.