The various changes that occur in the body during adolescence marks the onset of:

Options

A. Adolescence
B. Puberty
C. Hormones
D. None of these

Explanation

To answer the question regarding the various changes that occur in the body during adolescence and what they mark the onset of, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Adolescence**:
- Adolescence is the transitional stage between childhood and adulthood. It is characterized by various physical, emotional, and social changes.

2. **Identifying Key Changes**:
- During adolescence, individuals experience significant changes such as growth spurts, development of secondary sexual characteristics, and changes in body composition.

3. **Recognizing Puberty**:
- The onset of these physical changes is specifically referred to as puberty. Puberty is the period during which a child's body matures into an adult body capable of sexual reproduction.

4. **Evaluating the Options**:
- The options provided include:
- **Adolescence**: Incorrect, as this is the overall period, not the specific onset.
- **Puberty**: Correct, as it specifically refers to the physical changes marking the transition.
- **Hormones**: Incorrect, as hormones are the chemical messengers that facilitate these changes but do not define the onset.
- **None of these**: Incorrect, as we have identified puberty as the correct answer.

5. **Conclusion**:
- The various changes that occur in the body during adolescence mark the onset of **puberty**.

### Final Answer:
The various changes that occur in the body during adolescence mark the onset of **puberty**.

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