**Core Concept**
Notching of ribs is a radiological sign that indicates erosion of the lower margin of the ribs due to increased pressure on the intercostal neurovascular bundle. This can be caused by various conditions that lead to abnormal movement or pressure on the ribs.

**Why the Correct Answer is Right**
Notching of ribs is typically seen in conditions that cause increased pressure on the intercostal neurovascular bundle, such as in chronic intercostal muscle strain or in conditions like polycythemia vera where there is an increased number of red blood cells leading to increased blood viscosity and consequently increased pressure on the intercostal vessels. The intercostal vessels and nerves run along the lower border of the ribs and can be compressed or eroded due to increased pressure.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because notching of ribs is indeed a common finding in conditions like fibrous dysplasia of bone, where there is abnormal bone growth and remodeling that can lead to erosion of the lower margin of the ribs.

**Option B:** This option is incorrect because notching of ribs can be seen in conditions like osteoporosis, where there is a decrease in bone density and strength, leading to increased susceptibility to fractures and erosion of the lower margin of the ribs.

**Option C:** This option is incorrect because notching of ribs can be seen in conditions like Marfan syndrome, where there is a genetic disorder that affects the body's connective tissue, leading to abnormalities in the structure and function of various organs and tissues, including the ribs.

**Clinical Pearl / High-Yield Fact**
Notching of ribs can be a sign of underlying conditions that affect the intercostal neurovascular bundle, and it is essential to consider this sign in the context of the patient's overall clinical presentation and medical history.

**Correct Answer: D**