Roles of Chlorine and Carbon in Water Purification

Steps:

• Identify chlorine's primary function: disinfection by killing harmful microbes like bacteria.
• Identify carbon's primary function: adsorption of organic impurities causing tastes and odors.
• Compare options to these roles, focusing on accurate pairings.
• Select the option matching both uses without errors.

Why C is correct:

• Chlorine acts as a disinfectant, oxidizing and killing microbes per standard water treatment protocols; activated carbon removes dissolved tastes via adsorption of volatile organics.

Why the others are wrong:

• A: Chlorine kills microbes, not sediments solids (that's coagulants like alum); carbon adsorbs organics, not oxygen.
• B: Chlorine does not cause sedimentation; carbon removes tastes, not via sedimentation.
• D: Chlorine kills microbes, but carbon adsorbs tastes/odors, not dissolved oxygen (that's aeration or chemicals).

Final answer: C