Contraceptive oral pills used by females help in birth control by :

Options

A. Klilling of ova
B. preventing ovulation
C. killing the sperms
D. Forming barrier between sperms and ova .

Answer

**Step-by-Step Solution:**

1. **Understanding Contraceptive Oral Pills**: Contraceptive oral pills are medications taken by females to prevent pregnancy. They usually contain hormones such as estrogen and progesterone.

2. **Mechanism of Action**: The primary way these pills work is by preventing ovulation. This means that they stop the ovaries from releasing an egg (ovum) during the menstrual cycle.

3. **Hormonal Regulation**: The hormones in the pills regulate the menstrual cycle and inhibit the natural hormonal signals that trigger ovulation.

4. **Impact on Sperm**: By preventing ovulation, these pills also reduce the chances of sperm meeting an egg, as there is no egg available for fertilization.

5. **Conclusion**: Therefore, the correct answer to the question of how contraceptive oral pills help in birth control is option B: preventing ovulation.

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