What is the primary purpose of a life jacket?

The primary purpose of a life jacket is to keep a person afloat in water and prevent drowning. Life jackets are designed with buoyant materials that ensure individuals remain on the surface of the water, which is critical in emergencies when someone falls overboard or becomes incapacitated. Their buoyancy significantly reduces the risk of drowning, allowing the wearer to stay above water until help arrives or they can swim to safety.

While some life jackets may provide minimal insulation against cold water, their main function is not to protect against hypothermia; therefore, that aspect is secondary compared to their primary life-saving purpose. Similarly, life jackets do not enhance speed or swimming efficiency, as their design focuses on buoyancy rather than aiding swimming techniques. Thus, the correct answer reflects the essential role of life jackets in ensuring safety on the water.