Cork is a derivative of

Options

A. Crock cambium (phellongen) or extra fascicular cambium
B. Vascular cambium
C. Fascicular cambium
D. Interfascicular cambium

Answer

To determine the derivative of cork, we can follow these steps:

### Step-by-Step Solution:

1. **Understand what cork is**: Cork is a specialized tissue that serves as a protective barrier for plants. It is known for being impermeable and buoyant, which makes it useful in various applications, including bottle stoppers and insulation.

2. **Identify the source of cork**: Cork is derived from a specific layer of the bark tissue in plants. This layer is known as the phellem, which is produced by the cork cambium.

3. **Define cork cambium**: Cork cambium, also known as phellogen, is a type of lateral meristematic tissue that generates cork (phellem) cells. It is responsible for the production of cork as the plant grows.

4. **Analyze the options**: The question provides several options:
- Cork cambium (or extra fascicular cambium)
- Fascicular cambium
- Intrafascicular cambium
- Vascular cambium

5. **Determine the correct answer**: Among the options, cork cambium (or extra fascicular cambium) is the correct answer because it directly produces cork cells. The other options relate to different types of cambium that contribute to the formation of vascular tissues (xylem and phloem) rather than cork.

### Final Answer:
Cork is a derivative of **cork cambium (or extra fascicular cambium)**.

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