Which ones show stipular modifications
(a) Spines of Zizyphus
(b) Tendrils in Smilax
(c) Tendrils in Nepenthes
(d) Spines in Argemone
(e) Thorn in Bougainvillea

Options

A. a and b
B. a and c
C. b and e
D. c and e

Answer

To determine which options show stipular modifications, we need to understand what stipular modifications are. Stipular modifications are changes that originate from the stipules, which are small leaf-like structures at the base of a leaf stalk (petiole). Let's analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding Stipular Modifications**:
- Stipular modifications refer to changes in the stipules of a plant, which can take various forms such as spines or tendrils.

2. **Analyzing Each Option**:
- **(a) Spines of Zizyphus**:
- The spines in Zizyphus are actually modified stipules. They serve the purpose of protection for the plant.
- **Conclusion**: This option shows stipular modification.

- **(b) Tendrils in Smilax**:
- The tendrils in Smilax are also modified stipules. They help the plant in climbing and provide support.
- **Conclusion**: This option shows stipular modification.

- **(c) Tendrils in Nepenthes**:
- The tendrils in Nepenthes are modifications of the leaves, not the stipules.
- **Conclusion**: This option does not show stipular modification.

- **(d) Spines in Argemone**:
- The spines in Argemone are modifications of the leaf margins, not the stipules.
- **Conclusion**: This option does not show stipular modification.

- **(e) Thorn in Bougainvillea**:
- The thorns in Bougainvillea are modified stems, not stipules.
- **Conclusion**: This option does not show stipular modification.

3. **Final Answer**:
- The options that show stipular modifications are **(a) Spines of Zizyphus** and **(b) Tendrils in Smilax**.

### Summary:
The correct answer is **(a) and (b)**, as both represent stipular modifications.

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