Leaves become modified into spines in :-

Options

A. Pea
B. Onion
C. Silk Cotton
D. Opuntia

Answer

To solve the question "Leaves become modified into spines in:", we will analyze each option provided and determine which plant has leaves that are modified into spines.

### Step-by-Step Solution:

1. **Understand the Question**: The question asks which plant has leaves that are modified into spines. This indicates that we are looking for a plant adaptation that helps in reducing water loss or protecting the plant.

2. **Evaluate Option A: Pea (Pisum sativum)**:
- In pea plants, the leaves are modified into tendrils, which are used for support.
- **Conclusion**: This option is incorrect as the leaves are not modified into spines.

3. **Evaluate Option B: Onion (Allium cepa)**:
- In onions, the leaves are modified into fleshy, succulent structures that store food.
- **Conclusion**: This option is also incorrect as the leaves are not modified into spines.

4. **Evaluate Option C: Silk Cotton (Bombax)**:
- Silk cotton trees have palmately compound leaves, and there is no modification of leaves into spines.
- **Conclusion**: This option is incorrect as well.

5. **Evaluate Option D: Opuntia (Cactus)**:
- In Opuntia, the leaves are indeed modified into spines. This adaptation helps in reducing water loss and protecting the plant from herbivores.
- **Conclusion**: This option is correct as it directly answers the question.

### Final Answer:
The correct answer is **D: Opuntia**.

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