**Core Concept**
Early adolescence typically refers to a period in human development where significant physical, emotional, and social changes occur. This stage is characterized by the onset of puberty, marked by the activation of the hypothalamic-pituitary-gonadal axis, leading to the secretion of sex hormones.

**Why the Correct Answer is Right**
The correct answer falls within the age range of 10-14 years, during which the body undergoes rapid changes, including growth spurts, changes in body composition, and the development of secondary sex characteristics. This is due to the increased production of sex hormones, such as testosterone and estrogen, which are regulated by the hypothalamic-pituitary-gonadal axis. The hypothalamus produces gonadotropin-releasing hormone (GnRH), which stimulates the pituitary gland to release luteinizing hormone (LH) and follicle-stimulating hormone (FSH), leading to the production of sex hormones in the gonads.

**Why Each Wrong Option is Incorrect**
**Option A:** This age group is typically considered late childhood, characterized by a more stable physical and emotional state, and is not considered early adolescence.
**Option B:** This age group is often classified as young adulthood, marked by the completion of physical growth and the establishment of independence.
**Option C:** This age group is generally considered early adulthood, characterized by the completion of physical growth and the establishment of a career and social relationships.

**Clinical Pearl / High-Yield Fact**
It's essential to note that the onset of puberty and the duration of adolescence can vary significantly among individuals, making it crucial for healthcare providers to consider the unique needs and developmental stages of each patient.

**Correct Answer: C. 10-14 years**