**Core Concept**
Exarticulation of teeth refers to the complete displacement of a tooth from its supporting alveolar bone, resulting in loss of attachment. This concept is crucial in dental trauma and orthodontics.

**Why the Correct Answer is Right**
Avulsion is the most severe form of tooth trauma, where the tooth is completely knocked out of its socket due to a sudden and forceful impact. This can occur in sports, falls, or other accidents. The periodontal ligament and surrounding bone are disrupted, leading to a significant risk of ankylosis, infection, or tooth loss if not promptly treated.

**Why Each Wrong Option is Incorrect**
**Option A:** Intrusion refers to the displacement of a tooth into the alveolar bone, which is the opposite of exarticulation.
**Option B:** Extrusion is the partial displacement of a tooth from its socket, where the tooth remains attached to the periodontal ligament, but is otherwise not related to exarticulation.
**Option C:** Sublimation is a chemical process where a substance changes directly from a solid to a gas, and has no relevance to dental terminology.

**Clinical Pearl / High-Yield Fact**
In cases of avulsion, immediate replantation and stabilization are crucial to promote healing and prevent ankylosis or root resorption. The American Association of Endodontists recommends immediate replantation and splinting for at least 7-10 days to ensure optimal outcomes.

**✓ Correct Answer: D. Avulsion**