The correct answer is: C. Removing odours.
Activated carbon is a highly porous form of carbon that has been processed to increase its surface area. This makes it very effective at adsorbing (or attracting and holding onto) molecules, including those that cause odours. Activated carbon is used in a variety of applications, including water filtration, air purification, and odor removal.
Option A is incorrect because activated carbon is not effective at disinfecting water. Disinfection requires the use of chemicals or other methods that kill harmful bacteria.
Option B is incorrect because activated carbon is not effective at removing hardness from water. Hardness is caused by minerals such as calcium and magnesium, which activated carbon cannot remove.
Option D is incorrect because activated carbon is not effective at removing corrosiveness from water. Corrosiveness is caused by dissolved minerals, which activated carbon cannot remove.
In conclusion, activated carbon is used for removing odours. It is not effective at disinfecting water, removing hardness, or removing corrosiveness.