Which of the following chemicals can be used under chemical methods for contraception ?

Options

A. Lactic acid
B. Boric acid
C. Citric acid
D. All of these

Answer

**Step-by-Step Solution:**

1. **Identify the Chemicals Listed**: The question presents three chemicals: lactic acid, boric acid, and citric acid. We need to determine if these can be used as chemical methods for contraception.

2. **Research Each Chemical**:
- **Lactic Acid**: This chemical is used in contraceptive gels. It works by lowering the pH in the vagina, which helps to reduce sperm motility, thus preventing fertilization.
- **Boric Acid**: While it is mentioned that boric acid can be used for contraception, it is important to note that it may have harmful effects, especially for nursing infants, as it can pass into breast milk.
- **Citric Acid**: Similar to lactic acid, citric acid is also used in conjunction with other substances (like potassium bitartrate) in gels for contraception. It also helps in lowering the pH and impeding sperm movement.

3. **Conclusion on Chemical Methods for Contraception**: Since all three chemicals (lactic acid, boric acid, and citric acid) have applications in contraception, the correct answer to the question is that all of them can be used as chemical methods for contraception.

4. **Final Answer**: Therefore, the answer to the question is "All of these" (option 4).

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