**Core Concept**
Lp(a) is a type of lipoprotein that transports cholesterol in the blood. Elevated levels of Lp(a) are associated with an increased risk of cardiovascular disease. The goal of therapy is to lower Lp(a) levels and reduce this risk.

**Why the Correct Answer is Right**
Mipomersen is a small interfering RNA (siRNA) that targets the apolipoprotein(a) gene, responsible for encoding the apolipoprotein(a) component of Lp(a). By inhibiting the production of apolipoprotein(a), mipomersen decreases the levels of Lp(a) in the blood. This mechanism is distinct from statins, which primarily lower LDL cholesterol.

**Why Each Wrong Option is Incorrect**
**Option A:** Fibrates, such as fenofibrate, primarily work by activating peroxisome proliferator-activated receptor-alpha (PPAR-alpha), which increases the breakdown of triglycerides and decreases very-low-density lipoprotein (VLDL) levels. They do not directly affect Lp(a) levels.
**Option B:** Cholestyramine is a bile acid sequestrant that lowers LDL cholesterol by binding to bile acids in the gut and preventing their reabsorption. It does not have a significant effect on Lp(a) levels.
**Option C:** Nicotinic acid (niacin) can raise HDL cholesterol and lower triglycerides, but it does not have a significant effect on Lp(a) levels.

**Clinical Pearl / High-Yield Fact**
Mipomersen is an example of a therapeutic agent that targets the apo(a) gene, demonstrating the potential for genetic therapies to treat lipid disorders.

**Correct Answer:** C. Mipomersen.