Concept:Chlorine acts as a disinfectant in municipal water treatment.Explanation:Chlorine is added to water to destroy pathogenic microorganisms.These germs can cause diseases such as cholera, typhoid, and hepatitis.By killing or inactivating these germs, chlorine makes the water safe for drinking.It does not prevent tooth decay or goitre, and it is not mainly used to remove colour or odour.Answer:C. kill germs