Contraceptive pills are very effective with lesser side-effects and are well accepted by the females. They work by

Options

A. Inhibiting ovulation
B. Inhibitating implantation
C. Altering the quality of cervical mucus to prevent/retard the entry of sperms
D. All of these

Answer

### Step-by-Step Solution:

1. **Understanding Contraceptive Pills**:
- Contraceptive pills are a form of hormonal contraception used by females to prevent pregnancy during sexual intercourse. They are designed to be effective with minimal side effects.

2. **Mechanism of Action**:
- Contraceptive pills primarily work through several mechanisms:
- **Inhibiting Ovulation**: The pills prevent the ovaries from releasing eggs (ovulation). Without the release of an egg, fertilization cannot occur.
- **Inhibiting Implantation**: If ovulation does occur, the pills can also prevent a fertilized egg from implanting in the uterus, thereby preventing pregnancy.
- **Altering Cervical Mucus**: The pills thicken the cervical mucus, making it more difficult for sperm to enter the uterus. This reduces the likelihood of sperm reaching any eggs that may have been released.

3. **Conclusion**:
- Therefore, contraceptive pills are effective in preventing pregnancy by inhibiting ovulation, inhibiting implantation, and altering the quality of cervical mucus to prevent sperm entry. All these mechanisms contribute to their effectiveness as a contraceptive method.

### Final Answer:
Contraceptive pills work by inhibiting ovulation, inhibiting implantation, and altering the quality of cervical mucus to prevent or retard the entry of sperm.

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