**Core Concept**
The 'Cour-en-Sabot' shape, also known as a boot-shaped heart, is a radiological sign associated with a specific congenital heart defect. This appearance is due to the abnormal orientation of the heart in the thoracic cavity. The underlying principle being tested is related to **congenital heart diseases** and their effects on cardiac anatomy.

**Why the Correct Answer is Right**
The correct answer is related to Tetralogy of Fallot, a congenital heart defect characterized by four key features: ventricular septal defect, pulmonary stenosis, right ventricular hypertrophy, and an **overriding aorta**. The 'Cour-en-Sabot' shape is a result of the right ventricular hypertrophy which displaces the cardiac apex upwards, giving the heart a boot-like appearance on chest radiographs.

**Why Each Wrong Option is Incorrect**
**Option A:** Is incorrect because it does not typically present with a 'Cour-en-Sabot' shape.
**Option B:** Does not characteristically display this radiological sign.
**Option C:** Is not associated with the boot-shaped heart appearance.

**Clinical Pearl / High-Yield Fact**
Tetralogy of Fallot is a classic congenital heart defect that presents with cyanosis due to the right-to-left shunt through the ventricular septal defect. The 'Cour-en-Sabot' sign is a key radiological feature that suggests this diagnosis.

**Correct Answer:** D. Tetralogy of Fallot.