**Core Concept**
Oral lesions are a manifestation of various systemic diseases, and their frequency can vary depending on the underlying condition. In some cases, oral lesions are a rare or uncommon feature, making it essential for clinicians to consider the differential diagnosis.

**Why the Correct Answer is Right**
The correct answer is **Herpes Zoster (Varicella-zoster virus)**. Herpes Zoster typically presents as a painful rash in a dermatomal distribution, and oral lesions are uncommon. When oral lesions do occur, they are usually seen in immunocompromised patients or those with atypical presentations. The virus primarily targets the trigeminal nerve, causing localized pain and inflammation.

**Why Each Wrong Option is Incorrect**
* **Option A:** **Behçet's Disease** is a systemic vasculitis that often presents with oral ulcers as a hallmark feature. Oral lesions are a common manifestation of Behçet's Disease.
* **Option B:** **Reiter's Syndrome (Reactive Arthritis)** is a form of arthritis that often presents with oral ulcers, conjunctivitis, and urethritis. Oral lesions are a frequent feature of Reiter's Syndrome.
* **Option C:** **Lichen Planus** is a mucocutaneous disease that commonly presents with oral lesions, including white patches, erythema, and ulcers. Oral lesions are a characteristic feature of Lichen Planus.

**Clinical Pearl / High-Yield Fact**
When evaluating oral lesions, consider the patient's overall clinical presentation, including systemic symptoms, to narrow down the differential diagnosis.

**Correct Answer:** C. **Lichen Planus**