What type of injuries are most common during rappelling?

Rope burns, falls, and improper landings are indeed the most common types of injuries that can occur during rappelling. Rope burns can happen due to the friction created when the rope slides against the skin, which is particularly common if a climber or rigger does not have a proper grip or is inexperienced. Additionally, falls can occur if the rappelling technique is not executed correctly or if there is a failure in communication or equipment, leading to serious injuries. Improper landings, on the other hand, can result from not properly assessing the landing zone or poor technique, potentially leading to ankle or knee injuries upon contact with the ground.

The other options focus on injuries that are less directly associated with the act of rappelling itself. For instance, while muscle strains and sprains can occur in various physical activities, they are not as inherent to the rappelling process. Head injuries from falls, though a concern in high-risk activities, are less common compared to the specific risks involved in rappelling. Finally, exposure injuries such as frostbite are largely related to environmental conditions rather than the method of descent itself. Thus, understanding the specific risks linked to rappelling is crucial for safety and injury prevention.