The changes which occur at adolescence are controlled by:

Options

A. Gland
B. Puberty
C. Hormones
D. Adam's apple

Explanation

**Step-by-Step Solution:**

1. **Understanding Adolescence**: Adolescence is the developmental stage that occurs between the ages of 11 to 18 years. During this period, individuals experience significant physical, emotional, and psychological changes.

2. **Identifying the Options**: The options provided are:
- A) Gland
- B) Puberty
- C) Hormones
- D) Adam's apple

3. **Analyzing Each Option**:
- **Option A: Gland** - While glands like the pancreas and thyroid do secrete hormones, they themselves do not directly control the changes during adolescence. Therefore, this option is incorrect.
- **Option B: Puberty** - Puberty refers to the period of sexual maturation, but it is not the controlling factor for the changes. Thus, this option is also incorrect.
- **Option C: Hormones** - Hormones are the chemical messengers in the body that regulate various functions, including the changes that occur during adolescence. In males, testosterone is the primary hormone, while in females, estrogen and progesterone play significant roles. This makes this option the correct answer.
- **Option D: Adam's apple** - The Adam's apple is a feature of the larynx and does not control the changes during adolescence. Therefore, this option is incorrect.

4. **Conclusion**: The changes that occur during adolescence are primarily controlled by hormones. Therefore, the correct answer is **C) Hormones**.

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