This is an example of root hydrophyte

Options

A. Nymphaea
B. Wolffia
C. Salvinia
D. Hydrilla.

Answer

**Step-by-Step Solution:**

1. **Understanding Root Hydrophytes**:
- A root hydrophyte is a type of aquatic plant whose roots are submerged in water while the leaves and flowers are above the water surface.

2. **Identifying Examples**:
- The video mentions several aquatic plants, including Nymphaea (water lily), Salvinia, Wolffia, and Hydrilla.

3. **Analyzing Each Plant**:
- **Nymphaea (Water Lily)**: The roots are submerged in water, and the leaves and flowers float on the surface. This fits the definition of a root hydrophyte.
- **Salvinia**: This plant floats on the water surface and does not have submerged roots.
- **Wolffia**: This is also a floating plant without submerged roots.
- **Hydrilla (Water Thyme)**: While it has roots, they are typically found at the bottom of the water body, and the plant can also float.

4. **Conclusion**:
- Among the examples provided, Nymphaea (water lily) is the only plant that meets the criteria of a root hydrophyte, as its roots are submerged in water while its leaves and flowers are above the surface.

**Final Answer**: The example of a root hydrophyte is **Nymphaea (water lily)**.

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