Which of these changes experienced by a female during puberty cannot be observed externally?

Options

A. Increase in height
B. Change in body shape
C. Development of acne on face
D. Development of sex organs

Answer

To answer the question, "Which of these changes experienced by a female during puberty cannot be observed externally?", we will analyze each option provided and determine whether the change is visible from the outside or not.

### Step-by-Step Solution:

1. **Understanding Puberty**:
- Puberty is a stage of development where individuals experience various physical changes. In females, these changes are classified into primary and secondary sexual characteristics.

2. **Identifying the Changes**:
- We need to evaluate the options given in the question to see which change cannot be observed externally.

3. **Option Analysis**:
- **Option A: Increase in Height**:
- This change is visible externally as individuals grow taller during puberty.
- **Option B: Change in Body Shape**:
- This change is also observable. Females experience widening of hips and changes in body shape during puberty.
- **Option C: Development of Acne on Face**:
- Acne is a visible change on the skin that occurs due to hormonal changes during puberty.
- **Option D: Development of Sex Organs**:
- This change refers to the internal development of reproductive organs such as ovaries, fallopian tubes, and uterus. These changes occur inside the body and are not visible externally.

4. **Conclusion**:
- The change that cannot be observed externally during puberty in females is **Option D: Development of Sex Organs**.

### Final Answer:
**The change experienced by a female during puberty that cannot be observed externally is the development of sex organs.**

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