Foetus is nourished by

Options

A. Placenta
B. Yolk
C. Blood
D. Phagocytosis.

Answer

**Step-by-Step Solution:**

1. **Understanding Fetal Nourishment**: The fetus requires a source of nourishment during its development in the womb. This nourishment is crucial for its growth and development.

2. **Identifying the Options**: The options provided are:
- A. Placenta
- B. Yolk
- C. Blood
- D. Phagocytosis

3. **Analyzing the Placenta**: The placenta is an organ that forms during pregnancy. It develops from the trophoblast layer of the embryo and the endometrial lining of the mother. Its primary functions include:
- Facilitating the exchange of nutrients and oxygen from the mother to the fetus.
- Removing waste products and carbon dioxide from the fetal blood.

4. **Considering Other Options**:
- **Yolk**: The yolk sac is involved in early development but does not provide nourishment for the fetus throughout the pregnancy.
- **Blood**: While blood is essential for transporting nutrients, it is not the direct source of nourishment for the fetus; that role is fulfilled by the placenta.
- **Phagocytosis**: This is a process used by certain cells to engulf and digest foreign particles, not related to fetal nourishment.

5. **Conclusion**: Based on the analysis, the correct answer is option A, the placenta, as it is the primary structure that nourishes the fetus during its development in the womb.

**Final Answer**: The fetus is nourished by **A. placenta**.

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