How do the pills work ?
(i) Inhibit ovulation and implantation
(ii) Alter the quality of cervical muscus to prevent or retard the entry of sperms
(iii) Inhibit spermatogenesis

Options

A. (i),(ii) and (iii)
B. (i) and (ii)
C. (ii) only
D. (iii) only

Explanation

To understand how the pills work, we will analyze each statement provided in the question step by step.

### Step-by-Step Solution:

1. **Understanding Oral Contraceptives:**
- Oral contraceptives, commonly known as "the pill," are hormonal medications taken by females to prevent pregnancy. They primarily work by influencing hormonal levels in the body.

2. **Analyzing Statement (i): Inhibit ovulation and implantation**
- The first function of the pills is to inhibit ovulation. This means that the pills prevent the ovaries from releasing an egg. If there is no egg, fertilization cannot occur.
- Additionally, if fertilization does happen, the pills also prevent the implantation of the fertilized egg into the uterine lining. This dual action effectively prevents pregnancy.
- **Conclusion:** This statement is correct.

3. **Analyzing Statement (ii): Alter the quality of cervical mucus to prevent or retard the entry of sperms**
- The pills also work by altering the quality of cervical mucus. They thicken the cervical mucus, which makes it more difficult for sperm to swim through the cervix and enter the uterus.
- By doing this, the pills further reduce the chances of sperm meeting an egg, thus preventing fertilization.
- **Conclusion:** This statement is also correct.

4. **Analyzing Statement (iii): Inhibit spermatogenesis**
- Spermatogenesis is the process of sperm formation that occurs in the testes of males. Since the pills are taken by females, they do not have any direct effect on the male reproductive system or the process of spermatogenesis.
- Therefore, this statement is incorrect as the pills do not inhibit spermatogenesis.
- **Conclusion:** This statement is incorrect.

5. **Final Evaluation:**
- Based on the analysis, statements (i) and (ii) are correct, while statement (iii) is incorrect. Therefore, the correct answer includes only the first two statements.

### Final Answer:
The correct answer is that the pills work by:
- (i) Inhibiting ovulation and implantation
- (ii) Altering the quality of cervical mucus to prevent or retard the entry of sperms