**Core Concept**
Early complete fusion of all cranial sutures is a significant radiological finding, often associated with certain pathological conditions. This phenomenon is characterized by premature closure of the cranial sutures, which can lead to various clinical manifestations. The underlying cause of this condition is often related to genetic or hormonal abnormalities.

**Why the Correct Answer is Right**
The correct answer is associated with Crouzon syndrome, a rare genetic disorder caused by mutations in the FGFR2 gene. This condition leads to premature fusion of the cranial sutures, resulting in a characteristic "cloverleaf" skull shape. The pathophysiology involves the abnormal activation of fibroblast growth factor receptors, which disrupts normal bone growth and development. The premature fusion of cranial sutures can lead to increased intracranial pressure, vision problems, and other systemic complications.

**Why Each Wrong Option is Incorrect**
**Option A:** Apert syndrome is a related condition that also involves premature fusion of cranial sutures, but it is caused by mutations in the FGFR2 gene and typically presents with more severe clinical manifestations.

**Option B:** Saethre-Chotzen syndrome is another genetic disorder that can be associated with premature fusion of cranial sutures, but it is caused by mutations in the TWIST1 gene and typically presents with milder clinical manifestations compared to Crouzon syndrome.

**Option D:** Muenke syndrome is a rare genetic disorder that can be associated with premature fusion of cranial sutures, but it is caused by mutations in the FGFR3 gene and typically presents with more variable clinical manifestations.

**Clinical Pearl / High-Yield Fact**
Premature fusion of cranial sutures can be associated with various genetic and hormonal disorders, and it is essential to recognize these conditions to provide proper management and treatment.

**Correct Answer:** C. Crouzon syndrome is a genetic disorder characterized by premature fusion of cranial sutures, leading to a characteristic "cloverleaf" skull shape.