Which of the following statements is true ?

Options

A. Vessels are unicellular and with narrow lumen
B. Vessels are multicellular and with wide lumen
C. Tracheids are unicellular and with wide lumen
D. Tracheids are multicellular and with narrow lumen

Answer

To determine which statement is true regarding vessels and tracheids in plants, we can analyze the provided options step-by-step.

### Step-by-Step Solution:

1. **Understanding Vascular Tissue**:
- Vascular tissue in plants is primarily composed of xylem and phloem. Xylem is responsible for the transport of water and minerals, while phloem transports food.

2. **Identifying Components of Xylem**:
- Xylem consists of several components, including tracheids and vessels.
- Tracheids are long, narrow cells that help in the conduction of water.
- Vessels are wider and more efficient in transporting water.

3. **Analyzing the Statements**:
- **Statement 1**: "Vessels are unicellular and with narrow lumen."
- This is incorrect because vessels are multicellular and have a wide lumen.
- **Statement 2**: "Vessels are multicellular and with wide lumen."
- This is correct as vessels are indeed multicellular and have a wide lumen.
- **Statement 3**: "Tracheids are unicellular and with wide lumen."
- This is incorrect; tracheids are not unicellular and do not have a wide lumen.
- **Statement 4**: "Tracheids are multicellular and with narrow lumen."
- This is incorrect because while tracheids are indeed multicellular, they do not have a wide lumen.

4. **Conclusion**:
- After analyzing all the statements, the only true statement is: "Vessels are multicellular and with wide lumen." Therefore, the correct answer is option B.

### Final Answer:
**Option B: Vessels are multicellular and with wide lumen.**

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