Which is not a character of klinefelter's syndrome ?

Options

A. Trisomy
B. Gynaecomastia
C. Mental retardation
D. Sterile individual

Answer

To solve the question "Which is not a character of Klinefelter's syndrome?", we will analyze the options provided and identify which one does not belong to the characteristics associated with Klinefelter's syndrome.

### Step-by-Step Solution:

1. **Understanding Klinefelter's Syndrome**:
- Klinefelter's syndrome is a genetic condition that affects males. It is typically caused by the presence of an extra X chromosome, resulting in a 47,XXY karyotype.

2. **Analyzing the Options**:
- **Option 1: Trisomy**:
- Klinefelter's syndrome is indeed a form of trisomy (specifically, trisomy of the X chromosome). Therefore, this is a character of Klinefelter's syndrome.
- **Option 2: Gynecomastia**:
- This condition, characterized by the development of breast tissue in males, is commonly observed in individuals with Klinefelter's syndrome due to hormonal imbalances. Thus, this is also a character of Klinefelter's syndrome.
- **Option 3: Mental Retardation**:
- While some individuals with Klinefelter's syndrome may experience learning difficulties, it is not universally characterized by mental retardation. This option is less definitive as a characteristic of Klinefelter's syndrome.
- **Option 4: Sterile Individual**:
- Males with Klinefelter's syndrome are often sterile due to testicular dysfunction. This is a recognized characteristic of the syndrome.

3. **Conclusion**:
- Based on the analysis, the option that is **not a character of Klinefelter's syndrome** is **Option 3: Mental Retardation**.

### Final Answer:
**Option 3: Mental Retardation** is not a character of Klinefelter's syndrome.

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