Opuntia is a mesophytic plant.

Answer

**Step-by-Step Solution:**

1. **Understanding Opuntia**: Begin by identifying what Opuntia is. Opuntia is commonly known as the cactus.

2. **Classification of Plants**: Understand the classification of plants based on their adaptations to environmental conditions. Plants can be classified as xerophytes, mesophytes, and hydrophytes based on their water requirements.

3. **Defining Xerophytes**: Xerophytes are plants that are adapted to survive in dry environments, such as deserts. They have special adaptations to minimize water loss, such as modified leaves (spines) and thickened stems.

4. **Defining Mesophytes**: Mesophytes are plants that thrive in environments with a moderate supply of water. They are not specifically adapted to very dry or very wet conditions and typically grow in terrestrial habitats.

5. **Conclusion**: Since Opuntia is a cactus, it is classified as a xerophytic plant, not a mesophytic plant. Therefore, the statement "Opuntia is a mesophytic plant" is false.

**Final Statement**: Opuntia is a xerophytic plant, not a mesophytic plant.

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