The function of copper ions in copper releasing IUD's is

Options

A. They suppress sperm motility and fertilising capacity of sperms.
B. They inhibit gametogenesis
C. They make uterus unsuitable for implantation
D. They inhibit ovulation.

Explanation

### Step-by-Step Solution

1. **Understanding Copper-Releasing IUDs**: Copper-releasing intrauterine devices (IUDs) are small, T-shaped devices inserted into the uterus to prevent pregnancy. They release copper ions, which have specific functions in the reproductive system.

2. **Function of Copper Ions**: The primary role of copper ions in these IUDs is to create an environment that is hostile to sperm. This means that they affect the movement and viability of sperm.

3. **Suppressing Sperm Motility**: One of the key functions of copper ions is to suppress sperm motility. This means that the sperm's ability to swim and reach the egg is significantly reduced, making fertilization less likely.

4. **Fertilizing Capacity of Sperm**: In addition to affecting motility, copper ions also decrease the fertilizing capacity of sperm. This means that even if sperm reach the egg, their ability to fertilize it is compromised.

5. **Other Functions**: While the question presents other options such as inhibiting gametogenesis, making the uterus unsuitable for implantation, and inhibiting ovulation, these are not the primary functions of copper ions in copper-releasing IUDs.
- Inhibiting gametogenesis refers to the production of gametes, which is not directly affected by copper ions.
- Making the uterus unsuitable for implantation is more associated with hormone-releasing IUDs, not copper-releasing ones.
- Inhibiting ovulation is also not a direct effect of copper ions.

6. **Conclusion**: Therefore, the correct answer to the question is that the function of copper ions in copper-releasing IUDs is to suppress sperm motility and fertilizing capacity of the sperm.

### Final Answer
The function of copper ions in copper-releasing IUDs is to suppress sperm motility and fertilizing capacity of the sperm.

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