**Core Concept**
The cemento-enamel junction (CEJ) is the anatomical interface between the cementum covering the root of a tooth and the enamel covering the crown. Understanding the morphology of the CEJ is crucial in dental anatomy and restorative dentistry.

**Why the Correct Answer is Right**
The CEJ is a complex region where the cementum and enamel meet, but not always in a neat and orderly fashion. In some cases, the cementum may overlap the enamel, while in others, the enamel may cover the cementum. Furthermore, there are instances where the cementum and enamel do not meet at all, resulting in an open or diastema-like appearance. This variability is due to the unique morphology of each tooth and the individual's dental anatomy.

**Why Each Wrong Option is Incorrect**
**Option A:** Cementum meets enamel - While this can occur, it is not the only possibility, making this statement incomplete.
**Option B:** Cementum overlaps enamel - This can happen, but it's not the only scenario, and there are other possible arrangements.
**Option C:** Cementum does not meet enamel - This can also occur, but the correct answer encompasses all possible scenarios.

**Clinical Pearl / High-Yield Fact**
The CEJ is a critical area for restorative dentistry, as it can be a weak point in the tooth structure. Understanding the morphology of the CEJ is essential for proper tooth preparation and restoration.

**✓ Correct Answer: D. All of the above**