Adolescents age stas at the age of
**Core Concept**
The question refers to the definition of adolescence, a stage of human development that spans from puberty to adulthood. Adolescence is characterized by significant physical, emotional, and social changes. The World Health Organization (WHO) defines adolescence as the period between the ages of 10 and 19.
**Why the Correct Answer is Right**
Adolescence is a critical period of growth and development, marked by the onset of puberty. During this time, the body undergoes significant changes, including the development of secondary sexual characteristics, growth spurts, and changes in body composition. The onset of puberty typically begins between the ages of 9 and 14 in girls and 9 and 14 in boys. The definition of adolescence as starting at age 10 is based on the WHO's definition, which takes into account the physical, emotional, and social changes that occur during this period.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not align with the WHO's definition of adolescence.
* **Option B:** This option is incorrect because it is too young, as the onset of puberty typically begins between the ages of 9 and 14.
* **Option C:** This option is incorrect because it is too old, as the end of adolescence is typically defined as the age of 19.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that the definition of adolescence can vary across cultures and contexts. However, the WHO's definition provides a widely accepted framework for understanding this critical period of development.
**Correct Answer: D. 10**