**Core Concept**
Granulocytic sarcoma, also known as chloroma, is a rare extramedullary tumor composed of immature granulocytic cells. Immunohistochemical markers play a crucial role in diagnosing this condition. **Myeloperoxidase (MPO)** and **CD43** are commonly used markers for granulocytic sarcoma.

**Why the Correct Answer is Right**
Since the correct answer is not provided, let's discuss the general approach to solving this question. To determine the correct answer, we need to consider the typical immunohistochemical markers expressed by granulocytic sarcoma cells. **MPO**, **CD43**, and **CD117** are usually positive in granulocytic sarcoma.

**Why Each Wrong Option is Incorrect**
**Option A:** Without knowing the specific options, we can't provide detailed explanations. However, if an option like **CD3** (a T-cell marker) is listed, it would be incorrect because granulocytic sarcoma cells are of myeloid origin, not T-cell origin.
**Option B:** Similarly, if an option like **CD20** (a B-cell marker) is listed, it would be incorrect because granulocytic sarcoma cells are not of B-cell origin.
**Option C:** If an option like **Desmin** (a muscle marker) is listed, it would be incorrect because granulocytic sarcoma cells are not of muscle origin.
**Option D:** Without the specific options, we can't provide a detailed explanation.

**Clinical Pearl / High-Yield Fact**
Granulocytic sarcoma is often associated with **acute myeloid leukemia (AML)**, and its diagnosis can be challenging due to its variable presentation. Immunohistochemical markers like **MPO** and **CD43** are essential for establishing the diagnosis.

**Correct Answer:** Correct Answer: D. CD3