Oral contraceptives are used by females to check

Options

A. implantation
B. Fertillization
C. Ovulation
D. Entry of sperms in vagina .

Answer

### Step-by-Step Solution:

1. **Understanding Oral Contraceptives**:
- Oral contraceptives are pills taken by females to prevent pregnancy. They are typically composed of hormones, primarily estrogen and progesterone.

2. **Function of Oral Contraceptives**:
- The primary function of these pills is to control the female reproductive cycle, specifically to prevent ovulation.

3. **Hormonal Mechanism**:
- The hormones in the oral contraceptives work by inhibiting the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the pituitary gland. This inhibition prevents the ovaries from releasing an egg (ovulation).

4. **Preventing Fertilization**:
- Since no egg is released, there is no opportunity for fertilization to occur. Therefore, oral contraceptives effectively prevent pregnancy by stopping ovulation.

5. **Eliminating Other Options**:
- The question presents several options:
- **Implantation**: This is the process where a fertilized egg attaches to the uterus. Oral contraceptives do not prevent implantation since they primarily prevent ovulation.
- **Fertilization**: This is the union of the sperm and egg. If there is no egg due to the action of the contraceptives, fertilization cannot occur.
- **Entry of sperm into the vagina**: This is not affected by oral contraceptives, as they do not act as barriers.

6. **Conclusion**:
- The correct answer to the question is that oral contraceptives are used by females to check **ovulation**.