Select the incorrect statement.

Options

A. Tracheids are elongated dead cells having hard lignified walls
B. In few cases, end walls of vessels remain intact and possess several pores.
C. Grape vine has simple sieve plate whereas Euphorbia royleana has compound sieve plate.
D. Companion cells are thin walled living cells.

Explanation

To determine the incorrect statement among the options provided, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement A: Tracheids are elongated dead cells having hard lignified walls.**
- Tracheids are indeed elongated cells found in the xylem of plants. They are dead at maturity and have lignified walls, which help in the conduction of water.
- **Conclusion:** This statement is **correct**.

2. **Statement B: In few cases, ends of vessels remain intact and possess several pores.**
- Generally, the ends of xylem vessels are perforated to allow for efficient water transport. However, in some plants, the ends may remain intact and have pores. This is true for certain species.
- **Conclusion:** This statement is **correct**.

3. **Statement C: Grapevine has simple sieve plates whereas Euphorbia royalina has compound sieve plates.**
- This statement is incorrect. Grapevine (Vitis vinifera) actually has compound sieve plates, not simple ones. Euphorbia royalina also has compound sieve plates. Therefore, this statement misrepresents the sieve plate structure of grapevines.
- **Conclusion:** This statement is **incorrect**.

4. **Statement D: Companion cells are thin-walled living cells.**
- Companion cells are indeed thin-walled and living cells that assist in the function of sieve tubes in the phloem. They play a crucial role in the transport of nutrients.
- **Conclusion:** This statement is **correct**.

### Final Answer:
The incorrect statement is **C: Grapevine has simple sieve plates whereas Euphorbia royalina has compound sieve plates.**

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