**Core Concept**
Buerger disease, also known as thromboangiitis obliterans, is a rare disease of the arteries and veins in the arms and legs. The underlying pharmacological principle being tested involves the inflammatory processes affecting the blood vessels. This condition is characterized by a **segmental inflammatory process**.

**Why the Correct Answer is Right**
The correct answer is related to the fact that Buerger disease is a **panarteritis**, meaning it affects all layers of the artery, including the **intima**, **media**, and **adventitia**. This is due to the inflammatory process that involves the entire thickness of the arterial wall, leading to **thrombosis** and **occlusion** of the vessel.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because Buerger disease does not only affect one layer of the artery.
**Option B:** This option is also incorrect as the disease is not limited to just two layers of the arterial wall.
**Option D:** This option is incorrect because it does not accurately describe the layers of the artery affected by Buerger disease.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that Buerger disease typically affects small- and medium-sized arteries, and the diagnosis is often made based on a combination of clinical presentation and **angiographic findings**.

**Correct Answer:** C. All layers of the artery (intima, media, and adventitia).