**Core Concept**
Macrophages play a crucial role in the innate immune response, participating in the phagocytosis of foreign particles and the presentation of antigens to T-cells. They are also involved in the production of various cytokines and chemokines that regulate the immune response.

**Why the Correct Answer is Right**
Macrophages are a major source of tumor necrosis factor-alpha (TNF-α), a pro-inflammatory cytokine that plays a key role in the initiation and maintenance of inflammation. TNF-α is produced by macrophages in response to the recognition of pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) through pattern recognition receptors (PRRs) such as Toll-like receptors (TLRs). The production of TNF-α by macrophages leads to the activation of various signaling pathways that regulate the expression of inflammatory genes and the recruitment of immune cells to the site of inflammation.

**Why Each Wrong Option is Incorrect**
**Option A:** Interleukin-10 (IL-10) is an anti-inflammatory cytokine produced by regulatory T-cells, not macrophages.
**Option B:** Interferon-gamma (IFN-γ) is a cytokine produced by T-cells and natural killer cells, not macrophages.
**Option C:** Transforming growth factor-beta (TGF-β) is a cytokine involved in the regulation of cell growth and differentiation, not a primary product of macrophages.

**Clinical Pearl / High-Yield Fact**
TNF-α is a key mediator of the systemic inflammatory response syndrome (SIRS), a life-threatening condition that can occur in response to severe infection or trauma.

**Correct Answer: C. Tumor Necrosis Factor-alpha (TNF-α)**