Which one of the following can be determined by amniocentesis ?

Options

A. Turner's syndrome
B. Klinefelter's syndrome
C. Sex of the unborn child
D. All of the above

Answer

**Step-by-Step Solution:**

1. **Understanding Amniocentesis**: Amniocentesis is a medical procedure where amniotic fluid is extracted from the amniotic sac surrounding a developing fetus. This fluid contains fetal cells and various proteins.

2. **Purpose of Amniocentesis**: The primary purpose of amniocentesis is to test for chromosomal abnormalities and genetic disorders in the fetus. It can help identify conditions such as Down syndrome, cystic fibrosis, and other genetic disorders.

3. **Identifying Conditions**:
- **Turner Syndrome**: This is a chromosomal disorder caused by the absence of one X chromosome in females (45,X). Amniocentesis can detect this condition.
- **Klinefelter Syndrome**: This condition is caused by the presence of an extra X chromosome in males (47,XXY). Amniocentesis can also identify this syndrome.
- **Sex of the Unborn Child**: The procedure can determine the sex of the fetus by analyzing the chromosomes present in the fetal cells.

4. **Conclusion**: Since amniocentesis can determine Turner syndrome, Klinefelter syndrome, and the sex of the unborn child, the correct answer to the question is "all of the above."

**Final Answer**: All of the above.

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