**Core Concept**
The question requires knowledge of **pediatric oncology**, specifically the most common types of **extracranial solid tumors** found in children. This involves understanding the **epidemiology** and **pathophysiology** of various tumors.

**Why the Correct Answer is Right**
The most common extracranial solid tumor in children is **Neuroblastoma**, which arises from the **sympathetic nervous system**, often in the **adrenal glands** or **paraspinal regions**. It is known for its **variable presentation** and **prognosis**, which can range from **spontaneous regression** to **aggressive disease**.

**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because, although common, it is not specified and thus cannot be evaluated.
**Option B:** Incorrect as it is not provided.
**Option C:** Incorrect as the option is missing.
**Option D:** Incorrect as the option is not given.

**Clinical Pearl / High-Yield Fact**
It's crucial to remember that **Neuroblastoma** has a unique characteristic of potentially undergoing **spontaneous regression**, especially in infants, making it a **high-yield fact** for exams.

**Correct Answer:** D. Neuroblastoma