Many hydrophytes have production of different forms of leaves in the same plant i.e., heterophylly. In submerged aquatics with free-floating aerial leaves, the submerged leaves are generally linear, ribbon-shaped or finely dissected while the aerial leaves are complete and rounded or lobed.

So, the correct answer is " hydrophytes ".

Finely dissected leaves as an adaptation of hydrophytes

Hydrophytes are plants that are adapted to live in aquatic environments, such as ponds, lakes, and marshes. They have various adaptations that allow them to thrive in these water-rich environments, and one of these adaptations is the presence of finely dissected leaves.

Definition of finely dissected leaves
Finely dissected leaves are leaves that are deeply divided into numerous small leaflets or segments. These leaflets are often thin and have a high surface area to volume ratio.

Explanation of adaptation
The presence of finely dissected leaves in hydrophytes is considered an adaptation because it helps the plants overcome the challenges associated with living in water-rich environments.

Increased surface area
One advantage of finely dissected leaves is that they have a large surface area, which allows for increased absorption of sunlight. In aquatic environments, where light penetration is limited, the ability to capture more sunlight is crucial for photosynthesis. The increased surface area of finely dissected leaves enables hydrophytes to maximize their exposure to sunlight and optimize their energy production.

Optimized gas exchange
Another benefit of finely dissected leaves is that they facilitate efficient gas exchange. In aquatic environments, oxygen availability may be limited, and carbon dioxide diffusion can be slow. The finely divided leaflets of hydrophytes create a larger surface area for gas exchange, allowing them to efficiently take in carbon dioxide and release oxygen. This adaptation helps hydrophytes overcome the challenges associated with obtaining sufficient oxygen and carbon dioxide in water-rich environments.

Reduced water resistance
Finely dissected leaves also help hydrophytes reduce water resistance. In water, plants need to minimize drag and turbulence caused by water currents. The finely divided leaflets of hydrophytes create a more streamlined shape, reducing the resistance to water flow and allowing the plants to withstand water currents without being uprooted or damaged.

Conclusion
In conclusion, finely dissected leaves are an adaptation of hydrophytes. They provide increased surface area for sunlight absorption, optimize gas exchange, and reduce water resistance. These adaptations allow hydrophytes to thrive in aquatic environments by ensuring efficient energy production and minimizing the challenges associated with living in water-rich habitats.