**Core Concept**
Keloid scars are a type of raised, thickened skin scar that occurs when the body's healing process goes into overdrive, producing excessive collagen. This is due to an abnormal wound healing response, leading to an accumulation of collagen fibers and a characteristic raised appearance.

**Why the Correct Answer is Right**
The correct answer is **Hypertrophic collagen**. Keloid scars are composed of a dense, disorganized collection of collagen fibers, which are produced by an imbalance of collagen synthesis and degradation. This imbalance is mediated by various growth factors, including transforming growth factor-beta (TGF-β) and platelet-derived growth factor (PDGF), which stimulate collagen production and fibroblast proliferation.

**Why Each Wrong Option is Incorrect**
* **Option A:** Keloid scars are not made up of **Granulation tissue**, which is a type of tissue that forms during the inflammatory phase of wound healing, composed of new blood vessels, fibroblasts, and inflammatory cells.
* **Option B:** Keloid scars are not primarily composed of **Fibrin**, a protein that forms a network of fibers during the coagulation cascade, which is not the primary component of keloid scars.
* **Option C:** Keloid scars are not made up of **Dermal-epidermal junction**, which is the interface between the epidermis and dermis, but rather an abnormal accumulation of collagen fibers in the dermis.

**Clinical Pearl / High-Yield Fact**
Keloid scars can be challenging to treat, but silicone sheeting or pressure therapy can help reduce their size and appearance by inhibiting collagen synthesis and promoting collagen degradation.

**Correct Answer: C. Hypertrophic collagen**