**Core Concept**
Exanthema refers to a type of skin rash that can be caused by various factors, including medications. Drug-induced exanthema is a common adverse reaction to certain medications, and identifying the causative agent is crucial for managing the condition.

**Why the Correct Answer is Right**
The correct answer is a medication that can cause exanthema through various mechanisms, including immune-mediated reactions, allergic responses, or direct toxic effects on skin cells. The exact pathophysiology can vary depending on the specific medication, but it often involves the release of histamine and other inflammatory mediators, leading to increased blood flow, edema, and skin cell damage.

**Why Each Wrong Option is Incorrect**
* **Option A:** This medication is not commonly associated with exanthema. It is used to treat hypertension and has a different mechanism of action.
* **Option B:** While this medication can cause skin reactions, it is more commonly associated with photosensitivity and other types of cutaneous toxicity.
* **Option C:** This medication is not typically linked to exanthema. It is used in the treatment of certain infections and has a different pharmacological profile.

**Clinical Pearl / High-Yield Fact**
When evaluating a patient with a skin rash, it is essential to consider the possibility of a drug-induced exanthema, especially if the patient has recently started a new medication. A thorough history and physical examination can help identify the causative agent and guide appropriate management.

**Correct Answer:** D. **Piroxicam**, a nonsteroidal anti-inflammatory drug (NSAID), is a common cause of exanthema due to its immune-mediated effects and direct toxic effects on skin cells.