Contraceptive oral pills help birth control by

Options

A. Preventing ovulation
B. Killing the sperms
C. Forming barriers between sperms-ova
D. Killing the ova

Answer

**Step-by-Step Solution:**

1. **Understanding Contraceptive Oral Pills**: Contraceptive oral pills are medications taken by women to prevent pregnancy. They primarily work by altering hormonal levels in the body.

2. **Hormonal Composition**: These pills typically contain hormones such as progesterone, estrogen, or a combination of both. This hormonal change is crucial for their contraceptive effect.

3. **Preventing Ovulation**: The primary mechanism by which contraceptive oral pills prevent pregnancy is by inhibiting ovulation. This means that the pills prevent the release of an ovum (egg) from the ovaries.

4. **Suppressing Sperm Motility**: In addition to preventing ovulation, these pills can also affect sperm motility, making it more difficult for sperm to reach the egg.

5. **Cervical Mucus Alteration**: Contraceptive pills can change the consistency of cervical mucus, making it thicker. This thickened mucus acts as a barrier to sperm, preventing them from entering the uterus.

6. **Uterine Lining Modification**: The pills can also alter the lining of the uterus, making it less suitable for implantation should fertilization occur.

7. **Conclusion**: Based on these mechanisms, the primary way contraceptive oral pills help in birth control is by preventing ovulation. They do not kill sperm, do not kill ova, and do not create a physical barrier between sperm and ova.

**Final Answer**: Contraceptive oral pills help birth control by preventing ovulation.

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