Which of the following is a mechanical barrier used in birth control ?

Options

A. Loop
B. Dalkon shield
C. Copper-T
D. Diaphragm

Answer

To determine which of the following is a mechanical barrier used in birth control, we will analyze the options provided and identify the correct answer step by step.

### Step-by-Step Solution:

1. **Understanding Mechanical Barriers**: Mechanical barriers in birth control refer to devices that physically block sperm from reaching the egg. These include items like condoms and diaphragms.

2. **Evaluating the Options**:
- **Loop**: This typically refers to an intrauterine device (IUD), which is not a mechanical barrier but rather a device that prevents fertilization through hormonal or copper release.
- **Dalkon Shield**: This is also an intrauterine device that releases hormones and is not classified as a mechanical barrier.
- **Copper T**: Similar to the loop, the Copper T is an IUD that releases copper to prevent fertilization and is not a mechanical barrier.
- **Diaphragm**: This is a dome-shaped device that is inserted into the vagina before intercourse to cover the cervix and block sperm from entering the uterus. It is a mechanical barrier.

3. **Conclusion**: Based on the definitions and evaluations of the options, the diaphragm is the only device listed that functions as a mechanical barrier in birth control.

### Final Answer:
The mechanical barrier used in birth control is the **diaphragm**.

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