Which of the following is not a barrier?

Options

A. Vaginal ring
B. Cervical cap
C. Diaphragm
D. Vaults

Answer

To solve the question "Which of the following is not a barrier?" we will analyze each of the options provided.

### Step-by-Step Solution:

1. **Understand the Question**: We need to identify which option among the given choices does not function as a barrier method of contraception.

2. **List the Options**: The options provided are:
- A) Vaginal ring
- B) Cervical cap
- C) Diaphragm
- D) Walls

3. **Analyze Each Option**:
- **Option A: Vaginal Ring**: The vaginal ring is a hormonal birth control device made of flexible latex-free plastic. It releases hormones (progesterone and estrogen) to prevent ovulation. Since it does not act as a barrier to sperm, it is not a barrier method.

- **Option B: Cervical Cap**: The cervical cap is a barrier method that fits over the cervix and prevents sperm from entering the uterus. It does not release hormones and physically blocks sperm, making it a barrier method.

- **Option C: Diaphragm**: Similar to the cervical cap, the diaphragm is a dome-shaped barrier that covers the cervix to prevent sperm from entering. It is also a mechanical barrier method.

- **Option D: Walls**: This option is ambiguous, but if we consider "walls" as referring to the walls of the vagina or cervix, they are part of the anatomical structure and do not function as a contraceptive barrier method.

4. **Identify the Correct Answer**: Based on the analysis, the vaginal ring is the only option that is not a barrier method of contraception. Therefore, the correct answer is:
- **A) Vaginal Ring**

### Final Answer:
The option that is not a barrier is **A) Vaginal Ring**.