**Core Concept**
In forensic medicine, the examination of gunshot wounds is crucial for reconstructing the events surrounding a shooting. Gunshot wounds can be categorized into entry and exit wounds, each with distinct characteristics. The exit wound is formed when the bullet exits the body, causing damage to the surrounding tissue.

**Why the Correct Answer is Right**
The correct answer is B. Abrasion collar, which refers to a ring of abrasions around the edge of the exit wound. This occurs due to the friction between the bullet and the skin as it exits the body, causing a ring of scraping or abrasion. The abrasion collar is a characteristic feature of exit wounds and can be seen in cases of gunshot trauma. The presence of an abrasion collar helps forensic experts to distinguish exit wounds from other types of wounds.

**Why Each Wrong Option is Incorrect**
**Option A:** A "di collar" is not a recognized term in forensic medicine, and it is unlikely to be associated with gunshot wounds.

**Option C:** Tattooing, also known as "stippling," is a characteristic feature of entry wounds, not exit wounds. It occurs when the bullet fragments or ricochets, causing tiny punctate wounds on the skin.

**Option D:** Inverted edges are not typically associated with gunshot wounds, and this description is more characteristic of other types of wounds, such as incisions or cuts.

**Clinical Pearl / High-Yield Fact**
When examining gunshot wounds, it is essential to note the presence or absence of an abrasion collar, as this can help distinguish between entry and exit wounds. This can be a critical piece of information in reconstructing the events surrounding a shooting.

**✓ Correct Answer: B. Abrasion collar**