_______are the green stems of limited growth which have taken over the function of photosynthesis form leaves.

Options

A. Phylloclades
B. Cladodes
C. Phyllodes
D. Stem thorns

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a specific term that describes green stems of limited growth that have taken over the function of photosynthesis from leaves.

2. **Analyzing the Options**: The options provided are:
- Phylloclades
- Cladodes
- Phyllodes
- Stem thorns

3. **Defining Each Term**:
- **Phyllodes**: These are flattened petioles of leaves that resemble leaf blades but are not stems.
- **Cladodes**: These are modified stems that take on the function of leaves, serving as photosynthetic organs.
- **Phylloclades**: These are flat, leaf-like structures that consist of multiple nodes and internodes, sometimes serving as water storage organs.
- **Stem Thorns**: These are modified stems that serve as a defense mechanism for the plant.

4. **Identifying the Correct Option**:
- Since the question specifically mentions "green stems of limited growth which have taken over the function of photosynthesis from leaves," the correct term is **Cladodes**. Cladodes are indeed modified stems that perform photosynthesis.

5. **Conclusion**: The correct answer to the question is **Cladodes**.

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