The birth control device used by women is

Options

A. diaphragm
B. vault
C. copper T
D. all of these

Explanation

**Step-by-Step Solution:**

1. **Understanding Birth Control Devices**: Begin by defining what a birth control device is. A birth control device, also known as a contraceptive device, is an instrument used to prevent pregnancy.

2. **Identifying the Options**: The options provided in the question are:
- Diaphragm
- Vault
- Copper T

3. **Explaining the Diaphragm and Vault**:
- Both the diaphragm and vault are barrier methods made of rubber.
- They are inserted into the female reproductive tract to cover the cervix during intercourse.
- Their primary function is to prevent sperm from entering the uterus, thereby preventing conception.

4. **Explaining the Copper T**:
- The Copper T is an intrauterine device (IUD).
- It is T-shaped and made of copper.
- This device is inserted into the uterus and releases copper ions, which help prevent pregnancy.

5. **Conclusion**: Since all three options (diaphragm, vault, and copper T) are birth control devices used by women to prevent pregnancy, the correct answer to the question is that all of these are contraceptive devices.

6. **Final Answer**: Therefore, the answer to the question "The birth control device used by women is" is **all of these**.

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