Which type of open soft-tissue injury is limited to the superficial layer of the skin and results in the least amount of blood loss?

An abrasion is indeed the correct answer as it involves damage to the superficial layers of the skin, specifically the epidermis and sometimes the upper part of the dermis. This type of injury typically occurs when the skin is scraped against a rough surface, resulting in minimal bleeding due to the fact that it does not penetrate deeply into the blood vessels found in the deeper layers of the skin.

Abrasion injuries are common in various scenarios, such as falls or outdoor activities, and they tend to heal with little intervention since they do not impact deeper structures. The body's natural healing processes can manage these minor injuries effectively, making abrasions generally less severe compared to other open soft-tissue injuries, such as avulsions, incisions, and lacerations, which involve deeper tissue damage and greater potential for blood loss.