What is checked during the preflight for restraints?

In the context of preflight checks for restraints, the focus on the quantity required for safety is crucial. This ensures that there are enough restraints available for all personnel on board, which directly ties into safety protocols. Ensuring the correct quantity confirms that in the event of an emergency, every individual can be appropriately secured, reducing the risk of injury.

While other aspects aren't irrelevant, such as checking the overall condition of the restraints or ensuring they are appropriately sized, none is as critical as ensuring there are enough restraints for every person who will be on board. Properly assessing the quantity during a preflight check upholds safety standards and contributes to the overall preparedness of the flight.