Thorn of Citrus and Bougainvillea protect plants from browsing animals is modified-

Options

A. Stem
B. Root
C. Leaf
D. Bud

Answer

**Step-by-Step Solution:**

1. **Identify the Plant Structures**: Recognize that both Citrus (like orange trees) and Bougainvillea have thorns. These thorns are not leaves or roots but are modifications of the stem.

2. **Understand the Function of Thorns**: Thorns serve as a defense mechanism for the plants. They deter browsing animals from eating the leaves and stems, thus protecting the plant from damage.

3. **Classify the Modification**: Since thorns are derived from the stem tissue and not from leaves or roots, we classify them as stem modifications.

4. **Conclusion**: Therefore, the thorns of Citrus and Bougainvillea are modified stems that provide protection against herbivores.

5. **Select the Correct Option**: Based on the classification and function, the correct answer to the question is that the thorns are a modification of the stem.

**Final Answer**: The thorns of Citrus and Bougainvillea protect plants from browsing animals as modified stems.

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