In which of the following aquatic plant pollination does not occur by water?

Options

A. Vallisneria
B. Hydrilla
C. Water hyacinth
D. Zostera

Answer

To determine which aquatic plant does not rely on water for pollination, we can analyze the characteristics of various aquatic plants. Here’s a step-by-step solution:

### Step 1: Identify Aquatic Plants
Aquatic plants can be classified into two categories: freshwater plants and marine plants. Examples of freshwater plants include Vallisneria and Hydrilla, while marine plants may include species like seagrasses.

### Step 2: Understand Pollination Mechanisms
In many aquatic plants, pollination occurs through water. This means that the pollen grains are released into the water and carried by water currents to the flowers for fertilization.

### Step 3: Analyze Specific Plants
- **Vallisneria**: This plant has flowers that are located at the surface of the water. The pollen is released into the water, and water currents help in the transfer of pollen to the female flowers.
- **Hydrilla**: Similar to Vallisneria, Hydrilla also has a mechanism where pollen is released into the water, allowing for water-mediated pollination.
- **Water Hyacinth**: Unlike Vallisneria and Hydrilla, the water hyacinth does not submerge in water. Its flowers are above the water surface, and it does not depend on water for pollination.

### Step 4: Conclusion
Based on the analysis, the aquatic plant that does not rely on water for pollination is the **Water Hyacinth**. Therefore, the correct answer to the question is the Water Hyacinth.

### Final Answer:
Water Hyacinth does not occur by water for pollination.

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