**Core Concept**
A granulomatous reaction is a type of chronic inflammatory response characterized by the formation of granulomas, which are aggregates of immune cells, including macrophages, epithelioid cells, and giant cells. This response is typically seen in conditions such as tuberculosis, sarcoidosis, and foreign body reactions.

**Why the Correct Answer is Right**
The characteristic cell of a granulomatous reaction is the **epithelioid cell**, which is a modified macrophage that plays a crucial role in the formation and maintenance of granulomas. Epithelioid cells are derived from activated macrophages and are often seen in close association with lymphocytes, which helps to drive the immune response. The exact mechanism of granuloma formation is complex and involves the interaction of various immune cells and cytokines, including TNF-alpha, IFN-gamma, and IL-12.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because **neutrophils** are primarily involved in acute inflammatory responses, not chronic granulomatous reactions.
**Option B:** This option is incorrect because **lymphocytes** are involved in the immune response, but they are not the characteristic cell of a granulomatous reaction.
**Option C:** This option is incorrect because **giant cells** are a type of multinucleated cell that can be seen in granulomas, but they are not the characteristic cell of a granulomatous reaction.

**Clinical Pearl / High-Yield Fact**
A classic example of a granulomatous reaction is the formation of granulomas in the lungs in patients with tuberculosis. This is often accompanied by the presence of giant cells and a chronic inflammatory response.

**Correct Answer: C. Giant cells**