**Core Concept**
Saw-tooth rete ridges refer to a specific histopathological pattern observed in the skin, particularly in conditions characterized by epidermal-dermal junctional changes. This pattern is typically associated with autoimmune or inflammatory disorders that affect the skin.

**Why the Correct Answer is Right**
The saw-tooth rete ridges are a result of the epidermal-dermal junction being disrupted, leading to a characteristic "saw-tooth" appearance. This is often seen in conditions such as lichen planus, a chronic inflammatory condition that affects the skin and mucous membranes. In lichen planus, the epidermal-dermal junction is affected, leading to the formation of saw-tooth rete ridges due to the irregular arrangement of the rete ridges.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect as saw-tooth rete ridges are not typically associated with psoriasis, which is characterized by thickening of the epidermis and elongation of the dermal papillae.
* **Option B:** This option is incorrect as saw-tooth rete ridges are not a characteristic feature of seborrheic dermatitis, which is a chronic inflammatory condition affecting the scalp and other oily areas of the body.
* **Option C:** This option is incorrect as saw-tooth rete ridges are not typically associated with eczema, which is characterized by a complex interplay of genetic and environmental factors leading to inflammation and skin barrier disruption.

**Clinical Pearl / High-Yield Fact**
Saw-tooth rete ridges are an important histopathological feature that can help distinguish lichen planus from other conditions affecting the skin. This feature can be remembered by thinking of the "saw-tooth" appearance as a result of the irregular arrangement of the rete ridges, which is a hallmark of lichen planus.

**Correct Answer: D. Lichen planus**