cambium ring consists of

Options

A. interfascicular cambium
B. intrafascicular cambium
C. both A and B
D. phelloderm

Answer

### Step-by-Step Solution:

1. **Understanding Cambium**: The cambium is a layer of tissue in plants that is responsible for secondary growth. It is a type of meristematic tissue, which means it is capable of cell division.

2. **Types of Cambium**: In dicotyledonous plants, there are two types of cambium:
- **Intrafascicular Cambium**: This cambium is located between the xylem and phloem within a vascular bundle.
- **Interfascicular Cambium**: This cambium is found between the vascular bundles.

3. **Formation of Cambium Ring**: During secondary growth in dicotyledonous stems, the intrafascicular and interfascicular cambium join together to form a continuous ring known as the vascular cambium.

4. **Composition of the Cambium Ring**: The cambium ring consists of both:
- **Intrafascicular Cambium** (primary meristem)
- **Interfascicular Cambium** (secondary meristem)

5. **Conclusion**: Therefore, the cambium ring is composed of both intrafascicular and interfascicular cambium, which leads us to the final answer.

### Final Answer:
The cambium ring consists of both intrafascicular cambium and interfascicular cambium (both A and B).

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