What is the primary purpose of the drag litter?

The primary purpose of the drag litter is to facilitate the movement of the casualty. This type of equipment is specifically designed to carry injured individuals safely and efficiently from a site of injury to a safe location or medical facility. Drag litters allow for the quick evacuation of casualties, which is crucial on the battlefield or in emergency situations, where time is often of the essence. The design typically enables multiple rescuers to maneuver the litter easily over various terrains, ensuring that the injured person can be transported without further aggravating their injuries.

While other options mention aspects like speed or comfort, they do not directly address the litter’s main function. The drag litter's effectiveness is rooted in its ability to move casualties quickly and safely, ensuring they receive the necessary medical attention as soon as possible.