In Bougainvillea, thorns are the modifications of

Options

A. stipules
B. adventitious root
C. stem
D. leaf

Answer

**Step-by-Step Solution:**

1. **Identify the Plant**: The question refers to Bougainvillea, a flowering plant known for its vibrant colors.

2. **Understand the Structure**: In Bougainvillea, the flowers are surrounded by colorful structures. These colorful structures are known as bracts, which are modified leaves.

3. **Recognize the Role of Thorns**: Bougainvillea also has thorns, which are sharp, pointed structures that serve a protective function.

4. **Determine the Origin of Thorns**: The thorns in Bougainvillea are not leaves or bracts; they are actually modifications of the stem.

5. **Purpose of Thorns**: The primary purpose of these thorns is to protect the plant from herbivores or grazing animals that might damage the flowers or the plant itself.

6. **Conclusion**: Therefore, in Bougainvillea, the thorns are modifications of the stem.

**Final Answer**: In Bougainvillea, thorns are modifications of the stem.

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