A modification of leaf is

Options

A. Phyllode
B. Phylloclade
C. Cladode
D. Corm.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks for a modification of a leaf. We need to identify which of the given options represents a modified leaf structure.

2. **Analyzing the Options:**
The options provided are:
- A) Phyllode
- B) Phylloclad
- C) Cladode
- D) Comb

3. **Examining Option A: Phyllode**
- A phyllode is a modification of the leaf rachis or petiole.
- In xerophytic plants, the petiole becomes flattened and takes on the role of the leaf, performing photosynthesis and reducing transpiration.
- Therefore, phyllode is indeed a modification of a leaf.

4. **Examining Option B: Phylloclad**
- A phylloclad is a modification of the stem, not the leaf.
- It serves a similar function to leaves but is derived from the stem structure.

5. **Examining Option C: Cladode**
- A cladode is also a modification of the stem.
- Like phylloclad, it performs photosynthesis but is not a leaf modification.

6. **Examining Option D: Comb**
- A comb is an underground storage organ and is a modification of the stem.
- It does not represent a modification of a leaf.

7. **Conclusion:**
Based on the analysis, the only option that represents a modification of a leaf is **Option A: Phyllode**.

**Final Answer:**
The modification of a leaf is **Phyllode**.

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