Which of the following is a method for treating water to make it potable?

The chlorine disinfection method is widely recognized as an effective means for treating water and making it safe for human consumption. Chlorine is added to water to kill or inactivate harmful microorganisms, including bacteria, viruses, and protozoans that can cause waterborne diseases. This method is significant because it not only disinfects but also provides residual protection, ensuring that microorganisms do not re-enter the water supply after treatment.

Chlorine is relatively inexpensive and easy to deploy, making it a popular choice for municipalities and water treatment facilities around the world. When treated properly, chlorine can effectively eliminate threats to human health that may arise from contaminated water sources, thereby rendering the water potable.

Other methods, while useful in certain contexts, serve different purposes. For instance, ultraviolet radiation is effective at disinfecting water but does not provide the same residual protection that chlorine does. Air stripping is generally used to remove volatile organic compounds rather than treating biological contaminants, and activated carbon filtration is mainly employed for removing chemicals and impurities but may not be sufficient alone for disinfection. Thus, when assessing methods specifically aimed at making water potable, the chlorine disinfection method stands out as a robust and reliable solution.