Vascular combium is a lateral meristem and gives rise to

Options

A. primary xylem and primary phleom
B. more of secondary xylem on inner side and less of secondary phleom on outer side
C. less of secondary phleom on inner side and more secondary xylem on outer side
D. secondary phloem only

Answer

### Step-by-Step Solution:

1. **Understanding Vascular Cambium**:
- Vascular cambium is a type of lateral meristem found in plants. It is responsible for the secondary growth of stems and roots.

2. **Location of Vascular Cambium**:
- It is located between the primary xylem and primary phloem in the vascular bundles.

3. **Function of Vascular Cambium**:
- The primary function of vascular cambium is to produce secondary xylem (wood) and secondary phloem (part of the bark). This process increases the thickness of the plant.

4. **Secondary Growth Process**:
- During secondary growth, the vascular cambium divides to form new cells. It produces more secondary xylem towards the inner side and less secondary phloem towards the outer side.

5. **Result of Vascular Cambium Activity**:
- As a result of its activity, there is a greater accumulation of secondary xylem compared to secondary phloem. This is why the diameter of the stem and root increases over time.

6. **Analyzing the Options**:
- Given the options:
- A) Primary xylem and primary phloem
- B) More of secondary xylem on inner side and less of secondary phloem on outer side
- C) Less of secondary phloem on inner side, more secondary xylem on outer side
- D) Secondary phloem only
- The correct option is B, as it accurately describes the production of more secondary xylem on the inner side and less secondary phloem on the outer side.

### Final Answer:
The vascular cambium gives rise to **more of secondary xylem on the inner side and less of secondary phloem on the outer side** (Option B).

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