**Core Concept**
The relationship between enamel and cementum, the two hard tissues covering the crown and root of a tooth, is crucial for understanding tooth structure and development. Enamel is the hardest substance in the human body, covering the crown of the tooth, while cementum is a thin layer that covers the root of the tooth, facilitating attachment to the surrounding bone.

**Why the Correct Answer is Right**
Enamel and cementum meet at the cemento-enamel junction (CEJ), which marks the boundary between the crown and the root of the tooth. However, due to the unique shape and development of the tooth, it is rare for enamel to overlap cementum at this junction. This is because the enamel of the crown and the cementum of the root grow at different rates and in different directions, resulting in a slight gap or overlap at the CEJ. In most cases, the cementum is thicker than the enamel at the CEJ, but in some instances, enamel may overlap the cementum, making option B a rare occurrence.

**Why Each Wrong Option is Incorrect**
**Option A:** This is the normal relationship between enamel and cementum at the CEJ, where they meet at a point.

**Option C:** Cementum overlapping enamel is not a characteristic feature of the CEJ.

**Option D:** Enamel and cementum do meet at the CEJ, but it is not a universal rule that they never meet.

**Clinical Pearl / High-Yield Fact**
It is essential for dentists and oral surgeons to be aware of the CEJ and its relationship with enamel and cementum to diagnose and treat conditions such as tooth decay, periodontal disease, and root fractures.

✓ Correct Answer: B. Enamel overlaps cementum.