The number of sex chromosomes is found to be normal in

Options

A. Super female
B. Turner's syndrome
C. Klinefelter's syndrome
D. Down's syndrome

Answer

To solve the question "The number of sex chromosomes is found to be normal in," we will analyze each of the provided options step by step.

### Step 1: Analyze the Super Female
- **Definition**: A super female is characterized by having three X chromosomes (XXX).
- **Normal Condition**: Normal females typically have two X chromosomes (XX).
- **Conclusion**: The number of sex chromosomes in super females is not normal since they have an extra X chromosome.

### Step 2: Analyze Turner Syndrome
- **Definition**: Turner syndrome occurs in females who typically have only one X chromosome (X0).
- **Normal Condition**: Normal females have two X chromosomes (XX).
- **Conclusion**: The number of sex chromosomes in Turner syndrome is not normal since they are missing one X chromosome.

### Step 3: Analyze Klinefelter Syndrome
- **Definition**: Klinefelter syndrome occurs in males who have an extra X chromosome (XXY).
- **Normal Condition**: Normal males have one X and one Y chromosome (XY).
- **Conclusion**: The number of sex chromosomes in Klinefelter syndrome is not normal since they have an extra X chromosome.

### Step 4: Analyze Down Syndrome
- **Definition**: Down syndrome is caused by an extra copy of chromosome 21 (trisomy 21).
- **Normal Condition**: Individuals typically have two copies of chromosome 21.
- **Sex Chromosomes**: Down syndrome does not involve any abnormalities in the sex chromosomes; individuals can have a normal set of sex chromosomes (XX or XY).
- **Conclusion**: The number of sex chromosomes in Down syndrome is normal.

### Final Answer
Based on the analysis of all options, the number of sex chromosomes is found to be normal in **D. Down syndrome**.

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