Chlorine is used for which of the following purposes?

Chlorine is widely used for sterilizing water supplies due to its effective disinfectant properties. When chlorine is added to water, it forms hypochlorous acid, which is a powerful oxidizing agent that can kill a range of pathogens, including bacteria and viruses. This process is crucial for making drinking water safe and for maintaining sanitary conditions in swimming pools and other recreational water facilities.

In contrast, while chlorine does have indirect impacts on food preservation through its use in sanitizing surfaces and equipment, it is not used directly as a preservative in food products. The other options, such as fuel production and plant growth, do not involve chlorine as a primary function. Chlorine's primary role is specifically linked to its disinfecting ability, making it essential for maintaining public health through safe water supplies.