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. **Understanding Contraception**:
- Contraception refers to methods used to prevent childbirth. It can be achieved through various means, including chemical methods, natural methods, and physical barriers.

2. **Identifying Chemical Methods**:
- Among the various types of contraceptive methods, chemical methods are those that involve the use of specific chemicals to prevent sperm from fertilizing an egg.

3. **Spermicides**:
- One of the primary chemical methods of contraception is the use of spermicides. These are substances that kill sperm or inhibit their movement, thereby preventing fertilization.

4. **Types of Spermicides**:
- Spermicides come in various forms, including foams, jellies, creams, and douches. They contain active ingredients that act as killing agents for sperm.

5. **Examples of Spermicides**:
- Some common examples of spermicides include:
- Lactic acid
- Boric acid
- Citric acid
- Zinc sulfate
- Potassium permanganate

6. **Conclusion**:
- In the context of the question, if the options provided include lactic acid, boric acid, and citric acid, then all of these are valid examples of chemicals used in contraception through chemical methods. Therefore, the correct answer would be "All of these."