What is the primary function of seat belts during flight operations?

The primary function of seat belts during flight operations is to enhance passenger safety. Seat belts are essential safety devices that help to keep passengers securely in their seats during turbulence, sudden stops, or any unexpected events that may occur during flight. When an aircraft experiences turbulence, the forces can cause passengers to be thrown from their seats, potentially leading to injuries. By wearing a seat belt, passengers are protected from these forces, which significantly reduces the risk of harm.

The other options do not address the primary role of seat belts in flight operations. While seat belts might have an indirect effect on the efficiency of boarding by keeping passengers seated and preventing movement, their main purpose is centered around safety. Similarly, seat belts do not contribute to fuel efficiency or serve merely to restrict movement; rather, they are designed to ensure that individuals remain safely secured in their seats, thereby enhancing overall safety during flight.