Preventice birth control measure is :

Options

A. Preventing union of sperm and ovum
B. preventing sperms from entering uterus
C. MTP
D. Test tube babies .

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a preventive birth control measure. This means we are looking for a method that prevents pregnancy from occurring.

2. **Analyzing the Options**:
- **Option A: Preventing union of sperm and ovum**: This option refers to methods that prevent fertilization from occurring. This is a direct preventive measure against pregnancy.
- **Option B: Preventing sperms from entering uterus**: This option also refers to preventive measures, such as condoms or cervical caps, which aim to block sperm from reaching the egg. However, it does not guarantee that fertilization won't occur if sperm were to enter.
- **Option C: MTP (Medical Termination of Pregnancy)**: This is a procedure to terminate an existing pregnancy, not a preventive measure.
- **Option D: Test tube babies**: This refers to assisted reproductive technology for couples who are infertile; it does not prevent pregnancy but rather assists in conception.

3. **Evaluating the Options**:
- **Option A** is a clear preventive measure as it directly prevents fertilization.
- **Option B** is also preventive but is less direct as it focuses on preventing sperm entry rather than preventing the union of sperm and egg.
- **Option C** is not preventive but rather a post-conception action.
- **Option D** does not relate to prevention but to conception.

4. **Conclusion**: After evaluating all options, the best answer that fits the definition of a preventive birth control measure is **Option A: Preventing union of sperm and ovum**.

**Final Answer**: A. Preventing union of sperm and ovum.

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