Leaves become modified into spines in :-

Options

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

Answer

To answer the question "Leaves become modified into spines in:", we can follow these steps:

### Step 1: Understand the Concept of Modification
- Leaves can undergo modification for various reasons, primarily for adaptation to specific environmental conditions. In certain plants, leaves may transform into spines to help the plant survive in harsh conditions.

### Step 2: Identify the Options
- The options provided are pea, onion, silk cotton, and opuntia. We need to analyze each option to determine if the leaves are modified into spines.

### Step 3: Analyze Each Option
1. **Pea**: Pea plants do not have spines; their leaves are typically broad and perform photosynthesis.
2. **Onion**: Onion plants have bulbous structures and do not have modified leaves in the form of spines.
3. **Silk Cotton**: Silk cotton plants do not exhibit spines as a modification of their leaves.
4. **Opuntia**: Opuntia, commonly known as cactus, is a xerophytic plant that grows in dry conditions. In Opuntia, the leaves are modified into spines.

### Step 4: Conclusion
- The correct answer is **Opuntia**. The modification of leaves into spines in Opuntia helps reduce water loss and provides protection against herbivores.