The test-tube baby programme employes which one of the following techniqes ?

Options

A. intra cytoplasmic -sperm injection (ICSI)
B. Intra uterine insemination (IUI)
C. Gamete intra fallopian transfer (GIFT)
D. Zygote intra fallopian transfer (ZIFT)

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which technique is employed in the test-tube baby program. The term "test-tube baby" typically refers to assisted reproductive technologies.

2. **Identifying the Techniques**: The options provided include:
- ICSI (Intracytoplasmic Sperm Injection)
- Intrauterine Insemination
- Gamete Intrafallopian Transfer (GIFT)
- Zygote Intrafallopian Transfer (ZIFT)

3. **Defining the Test-Tube Baby Program**: The test-tube baby program primarily involves In Vitro Fertilization (IVF), where fertilization occurs outside the female body.

4. **Explaining ZIFT**: In Zygote Intrafallopian Transfer (ZIFT), fertilization occurs outside the body, and once the zygote is formed (usually at the 8-cell stage), it is transferred into the fallopian tube. This technique is also referred to as tubal embryo transfer.

5. **Analyzing the Options**:
- ICSI is a technique used in conjunction with IVF but is not the primary method for the test-tube baby program.
- Intrauterine insemination is a different technique and does not involve fertilization outside the body.
- GIFT involves placing gametes directly into the fallopian tubes but is not the main technique used in the test-tube baby program.
- ZIFT is specifically designed for transferring zygotes into the fallopian tubes after fertilization outside the body.

6. **Conclusion**: Based on the definitions and explanations, the correct answer is Zygote Intrafallopian Transfer (ZIFT), which is employed in the test-tube baby program.

**Final Answer**: D. Zygote Intrafallopian Transfer (ZIFT)

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