Which part of the cactus plant is modified into spine?

Options

A. Stem
B. Roots
C. Leaves
D. Branches

Explanation

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks which part of the cactus plant is modified into spines.

2. **Understand the Structure of the Cactus**: Cacti are unique plants that have adapted to survive in arid environments. They have specific modifications to help them conserve water.

3. **Recognize the Modified Part**: In cacti, the leaves are the parts that have been modified. Instead of having broad leaves like many other plants, cacti have spines.

4. **Explain the Reason for Modification**: The modification of leaves into spines serves a crucial purpose. It reduces the surface area of the plant, which in turn minimizes water loss due to evaporation or transpiration. This is especially important for cacti, which thrive in dry, desert conditions.

5. **Conclude with the Correct Answer**: Therefore, the part of the cactus plant that is modified into spines is the leaves.

**Final Answer**: The leaves of the cactus plant are modified into spines.

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