In which of the following disorder gynaecomastia sympton is seen in individuals

Options

A. Down's syndrome
B. Turner's syndrome
C. Klinefelter's syndrome
D. Phenylketonuria

Answer

### Step-by-Step Solution:

1. **Identify the Symptoms**: The question asks about the disorder associated with the symptom of gynecomastia, which is the abnormal development of breast tissue in males.

2. **Review the Options**: The options provided in the question include various genetic disorders. We need to analyze each option to determine which one is linked to gynecomastia.

3. **Understand Klinefelter Syndrome**: Klinefelter syndrome is a chromosomal disorder characterized by the presence of an extra X chromosome in males, resulting in a karyotype of XXY instead of the typical XY. This chromosomal anomaly can lead to various symptoms, including gynecomastia.

4. **Analyze Other Disorders**:
- **Down Syndrome**: This is caused by trisomy of chromosome 21 and does not typically present with gynecomastia.
- **Turner Syndrome**: This affects females and is characterized by a single X chromosome (XO). It does not involve gynecomastia.
- **Phenylketonuria (PKU)**: This is a metabolic disorder caused by a deficiency in the enzyme phenylalanine hydroxylase and is not associated with gynecomastia.

5. **Conclusion**: Based on the analysis, Klinefelter syndrome is the only disorder listed that is associated with the symptom of gynecomastia in individuals.

### Final Answer:
The disorder in which gynecomastia symptoms are seen in individuals is **Klinefelter syndrome** (Option C).

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