**Core Concept**
Precocious puberty refers to the onset of pubertal changes before the age of 8 in girls and 9 in boys. This condition is characterized by premature activation of the hypothalamic-pituitary-gonadal (HPG) axis, leading to increased production of sex hormones.

**Why the Correct Answer is Right**
The correct answer is related to the pathophysiology of precocious puberty. The condition is often caused by central or peripheral causes that stimulate the HPG axis. Central causes include hypothalamic hamartomas, while peripheral causes include sex hormone-secreting tumors or McCune-Albright syndrome. The most characteristic feature of precocious puberty is the premature activation of the HPG axis, which leads to increased production of sex hormones such as estrogen and testosterone.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not directly relate to the pathophysiology of precocious puberty. While certain genetic disorders may be associated with precocious puberty, they are not the most characteristic feature of the condition.

**Option B:** This option is incorrect because it describes a different condition altogether. Growth hormone deficiency is a condition characterized by short stature and delayed growth, rather than premature puberty.

**Option C:** This option is incorrect because it describes a condition that is not directly related to precocious puberty. While certain genetic disorders may be associated with precocious puberty, they are not the most characteristic feature of the condition.

**Clinical Pearl / High-Yield Fact**
A key clinical pearl to remember is that precocious puberty can be caused by a variety of central and peripheral causes, and a thorough evaluation is necessary to identify the underlying cause. Imaging studies such as MRI may be necessary to rule out central causes such as hypothalamic hamartomas.

**Correct Answer:** C. McCune-Albright syndrome