**Core Concept**
Coarctation of the aorta is a congenital condition characterized by narrowing of the aortic isthmus, leading to increased resistance to blood flow and elevated blood pressure in the arms. In pregnancy, the increased cardiac output and blood volume can exacerbate the condition, making it essential to choose an anesthesia technique that minimizes further hemodynamic stress.

**Why the Correct Answer is Right**
Epidural anesthesia is the preferred technique for patients with coarctation of the aorta undergoing cesarean section. This is because epidural anesthesia provides effective pain relief with minimal impact on systemic vascular resistance, heart rate, and blood pressure. The sympathetic blockade achieved with epidural anesthesia reduces peripheral resistance, which is beneficial in patients with coarctation of the aorta. Additionally, epidural anesthesia allows for precise control of the level of sympathetic blockade, minimizing the risk of complications such as hypertension and cardiac ischemia.

**Why Each Wrong Option is Incorrect**
**Option A:** General anesthesia is not the preferred choice because it can cause significant increases in blood pressure and heart rate, which can exacerbate the coarctation of the aorta.
**Option B:** Combined spinal-epidural anesthesia may be associated with an increased risk of hypotension, which can be detrimental in patients with coarctation of the aorta.
**Option C:** Spinal anesthesia can cause a sudden increase in sympathetic blockade, leading to significant decreases in blood pressure and cardiac output, which can be hazardous in patients with coarctation of the aorta.

**Clinical Pearl / High-Yield Fact**
In patients with coarctation of the aorta, the anesthesiologist should aim to maintain a stable blood pressure and heart rate during the procedure by carefully titrating the epidural anesthesia and using vasopressors if necessary.

**Correct Answer:** C. Epidural anesthesia