Progestogens in the contraceptive pill :

Options

A. prevents ovulation
B. inhabits estogen
C. checks attachment of zygote endometrium
D. All of these

Answer

### Step-by-Step Solution:

1. **Understanding Contraceptive Pills**: Contraceptive pills, commonly known as oral contraceptives, are medications taken by women to prevent pregnancy. They usually contain hormones such as estrogen and progestogen (progesterone).

2. **Role of Progestogens**: Progestogens, particularly progesterone, play a crucial role in the mechanism of action of contraceptive pills. Their primary function is to prevent ovulation.

3. **Mechanism of Action**:
- **Prevention of Ovulation**: Progestogens inhibit the release of hormones necessary for ovulation. By doing so, they prevent the ovaries from releasing an egg.
- **Inhibition of Follicular Development**: Progestogens also inhibit the development of ovarian follicles, which are necessary for ovulation to occur.
- **Impact on Endometrium**: Progestogens alter the endometrial lining, making it less suitable for implantation of a fertilized egg, thereby preventing pregnancy.

4. **Conclusion**: Based on the roles of progestogens in contraceptive pills, the correct answer to the question is that progestogens primarily "prevent ovulation". Therefore, the answer is option A.