The youngest layer of secondary xylem lies

Options

A. Between pith and primary xylem
B. Just outside the vascular cambium
C. Just inside the vascular cambium
D. Just inside the cork cambium

Answer

To answer the question regarding the location of the youngest layer of secondary xylem, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Secondary Xylem**: Secondary xylem is formed as a result of secondary growth in plants, which occurs due to the activity of the vascular cambium.

2. **Identifying the Vascular Cambium**: The vascular cambium is a layer of meristematic tissue that is responsible for the production of secondary xylem (wood) and secondary phloem.

3. **Locating the Youngest Layer**: The youngest layer of secondary xylem is produced just inside the vascular cambium. As the vascular cambium divides, it adds new cells to the inside, which become the secondary xylem.

4. **Differentiating Between Layers**:
- The primary xylem is located towards the center of the stem, and the secondary xylem is formed outward from the vascular cambium.
- The mature part of the secondary xylem is found outside the youngest layer, which is just inside the vascular cambium.

5. **Conclusion**: Therefore, the youngest layer of secondary xylem lies just inside the vascular cambium.

### Final Answer:
The youngest layer of secondary xylem lies just inside the vascular cambium.

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