According to Histogen theory of Hanstein , cortex is derived from :

Options

A. Ground meristem
B. Corpus
C. Periblem
D. Plerome

Answer

### Step-by-Step Solution:

1. **Understanding Histogen Theory**: The Histogen theory, proposed by Hanstein, explains the origin of different tissues in plants. It categorizes the initial cells in the apical meristem into different groups called histogens.

2. **Identifying the Principal Tissues**: According to this theory, the three principal tissues that arise from these histogens are:
- Vascular tissue
- Cortex
- Epidermis

3. **Identifying the Histogens**: Each of these tissues is derived from specific groups of initial cells:
- The vascular tissue is derived from the **plurome**.
- The cortex is derived from the **pariblum**.
- The epidermis is derived from the **dermatogen**.

4. **Focusing on Cortex Development**: Since the question specifically asks about the origin of the cortex, we focus on the pariblum, which is the histogen responsible for the development of the cortex.

5. **Conclusion**: Therefore, according to the Histogen theory of Hanstein, the cortex is derived from the **pariblum**.

### Final Answer:
According to the Histogen theory of Hanstein, the cortex is derived from the **pariblum**.

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