Companion cells are

Answer

**Step-by-Step Solution:**

1. **Understanding Companion Cells:**
- Companion cells are specialized cells found in the phloem tissue of flowering plants. They play a crucial role in the transport of nutrients, particularly sugars.

2. **Location of Companion Cells:**
- Companion cells are located adjacent to sieve elements (sieve tubes) in the phloem. This proximity is essential for their function in assisting with the transport of food.

3. **Characteristics of Companion Cells:**
- Companion cells are small, thin-walled cells. They have a distinct structure that allows them to support the sieve elements.

4. **Nucleation Status:**
- Companion cells are **nucleated**, meaning they contain a nucleus. This is an important distinction because it differentiates them from sieve tube elements, which are typically enucleated (lack a nucleus).

5. **Living Status:**
- Companion cells are **living cells**. They remain functional and play an active role in the transport process, unlike some other cells in the phloem that may be dead.

6. **Conclusion:**
- Based on the characteristics and functions of companion cells, the correct answer to the question is that companion cells are **nucleated and living**.

**Final Answer:**
Companion cells are nucleated and living.

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