**Core Concept**
Transposition of great vessels (TGA) is a congenital heart defect where the two main arteries that carry blood away from the heart are reversed. This results in the aorta arising from the right ventricle and the pulmonary artery arising from the left ventricle, leading to cyanosis and potentially life-threatening complications. The definitive treatment of choice for TGA is surgical repair to correct the abnormal anatomy and ensure proper oxygenation of blood.

**Why the Correct Answer is Right**
The definitive treatment of choice for TGA is the arterial switch operation (ASO), which involves switching the positions of the aorta and pulmonary artery. This is achieved by using a specialized surgical technique that involves detaching the aorta and pulmonary artery from the ventricles, rotating them 180 degrees, and reattaching them to their respective ventricles. This procedure is typically performed in the first few weeks of life and has a high success rate in correcting the abnormal anatomy and ensuring proper oxygenation of blood.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the arterial switch operation is the definitive treatment of choice for TGA, not a palliative procedure.
**Option B:** This option is incorrect because the Blalock-Taussig shunt is a palliative procedure used to increase blood flow to the lungs in patients with TGA, but it is not the definitive treatment of choice.
**Option C:** This option is incorrect because the Norwood procedure is a surgical procedure used to treat hypoplastic left heart syndrome (HLHS), not TGA.

**Clinical Pearl / High-Yield Fact**
The arterial switch operation is a complex surgical procedure that requires precise technique and expertise to ensure successful outcomes. It is essential for surgeons to have experience with this procedure to achieve optimal results.

**Correct Answer:** C. Arterial switch operation