Which of the following is an example of a closed wound?

A contusion is indeed an example of a closed wound. It occurs when small blood vessels are damaged, leading to bleeding underneath the skin without breaking the skin's surface. This type of wound typically results from a blunt force trauma, causing bruising and swelling in the affected area. Since the skin remains intact, it is classified as a closed wound.

In comparison, other options such as abrasion, amputation, and puncture represent open wounds where the skin is broken, exposing underlying tissues to the environment, which distinguishes them from closed wounds. Understanding the differences between closed and open wounds is crucial for proper assessment and management in emergency situations.