Which ions are released by the IUDs so that they become toxic for the sperm?

Options

A. Iron
B. Cobalt
C. Copper
D. Magnesium

Answer

### Step-by-Step Solution:

1. **Understand the Question**: The question asks which ions released by Intrauterine Devices (IUDs) are toxic to sperm.

2. **Define IUD**: IUD stands for Intrauterine Device, which is a form of long-term birth control inserted into the uterus by a healthcare professional.

3. **Types of IUDs**: There are two main types of IUDs:
- **Copper IUDs**: These release copper ions into the uterus.
- **Hormonal IUDs**: These release hormones that prevent fertilization.

4. **Focus on Copper IUDs**: The question specifically pertains to the ions released by IUDs that are toxic to sperm. Copper IUDs, such as Copper-T and Copper-7, are known to release copper ions.

5. **Mechanism of Action**: The copper ions released by these IUDs create an environment that is toxic to sperm. This toxicity reduces sperm motility (the ability of sperm to move) and decreases their fertilizing capacity.

6. **Identify the Correct Ions**: Based on the information, the ions released by IUDs that are toxic to sperm are primarily **copper ions**.

7. **Conclusion**: Therefore, the answer to the question is that **copper ions** are released by IUDs, making them toxic to sperm.

### Final Answer:
The ions released by IUDs that become toxic for sperm are **copper ions**.

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