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 of the following aquatic plants does not rely on water for pollination, we will analyze each option provided.

1. **Vallisneria**: This is a submerged aquatic plant known for its unique reproductive strategy. Vallisneria relies on water for pollination, as its flowers are typically submerged and the male flowers float to the surface to release pollen, which then drifts to the female flowers.

2. **Hydrilla**: Similar to Vallisneria, Hydrilla is another aquatic plant that also uses water for its pollination process. The pollen is carried by water currents to reach the female flowers.

3. **Water Hyacinth**: Water hyacinth is an aquatic weed characterized by its beautiful and conspicuous flowers. Unlike Vallisneria and Hydrilla, water hyacinth does not rely on water for pollination. Instead, it is pollinated by insects, particularly bees, which are attracted to its showy flowers.

4. **Zostera**: This is another aquatic plant that utilizes water for its pollination. Like Vallisneria and Hydrilla, Zostera's reproductive process is also dependent on water currents to facilitate the transfer of pollen.

Based on the analysis of each option, the correct answer is **Water Hyacinth**, as it is the only plant among the options that does not rely on water for its pollination process.

**Final Answer: Water Hyacinth**