A test-tube baby means

Options

A. Fertilization and development both in uterus
B. Fertilization in vitro and then transplantation in uterus
C. A baby grown in test tube
D. Fertilized and developed embryo in test tube

Answer

### Step-by-Step Solution:

1. **Understanding the Term "Test Tube Baby":**
- A test tube baby refers to a baby that is conceived through a process known as in vitro fertilization (IVF). This means that the fertilization of the egg by the sperm occurs outside the human body.

2. **In Vitro Fertilization (IVF):**
- In IVF, the ovum (egg) is collected from the female and sperm is collected from the male. These are combined in a laboratory setting, which is referred to as "in vitro" (meaning "in glass").

3. **Fertilization Process:**
- Once the sperm fertilizes the egg, a zygote is formed. This zygote is then allowed to develop into an embryo in a controlled environment outside the body.

4. **Transplantation to the Uterus:**
- After the embryo has developed to a certain stage, it is then implanted into the uterus of the female. This process is known as transplantation.

5. **Development in the Uterus:**
- Once the embryo is implanted in the uterus, it continues to develop into a fetus and eventually into a baby. This stage of development occurs "in vivo" (meaning "within the living").

6. **Conclusion:**
- Therefore, a test tube baby is not grown in a test tube; rather, it is conceived through IVF, where fertilization occurs in vitro, and the embryo is later implanted into the uterus for further development.

### Final Answer:
A test tube baby means a baby that is conceived through in vitro fertilization, where fertilization occurs outside the body and the embryo is later implanted into the uterus for development.

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