Mark the correct option.

Options

A. Turner's syndrome -45+ XO
B. Thalassemia- 44+YO
C. Klinefelters syndrome - 44+XXY
D. Phenylketonuria- 44+XYY

Answer

To solve the question regarding the correct option among the given syndromes, let's analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding Turner Syndrome (Option A: 45 + X0)**:
- Turner syndrome occurs in females and is characterized by the presence of only one X chromosome (X0) and 44 autosomes.
- The correct chromosomal formula for Turner syndrome is 44 + X0, not 45 + X0.
- Therefore, Option A is incorrect.

2. **Understanding Thalassemia (Option B: 44 + Y0)**:
- Thalassemia is an autosomal disorder related to hemoglobin production and does not involve sex chromosomes.
- It is characterized by a normal set of autosomes (44) plus two sex chromosomes (XX or XY).
- The given option (44 + Y0) is incorrect as it implies a missing X chromosome, which is not applicable to thalassemia.
- Therefore, Option B is incorrect.

3. **Understanding Klinefelter Syndrome (Option C: 44 + XXY)**:
- Klinefelter syndrome occurs in males and is characterized by the presence of an extra X chromosome (XXY) along with 44 autosomes.
- The correct chromosomal formula for Klinefelter syndrome is indeed 44 + XXY.
- Therefore, Option C is correct.

4. **Understanding Phenylketonuria (Option D: 44 + XY)**:
- Phenylketonuria (PKU) is an autosomal recessive disorder caused by a deficiency in the enzyme that breaks down phenylalanine.
- It does not involve sex chromosomes and is characterized by 44 autosomes and either XX or XY sex chromosomes.
- The given option (44 + XY) is incorrect as it does not represent the disorder accurately.
- Therefore, Option D is incorrect.

### Conclusion:
The correct answer is **Option C: Klinefelter Syndrome (44 + XXY)**.

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