Which wetland plant is characterized by having 5 species in Florida with distinct leaf stalks?

Floatinghearts are the correct choice because they belong to the family of plants characterized by their distinctive leaf structure and growth form in wetland environments. In Florida, there are five species of floatinghearts, each identifiable by their unique leaf stalks. These plants have rounded, floating leaves that are attached to the water's surface by long petioles or leaf stalks, allowing them to thrive in aquatic systems.

The other options, while they represent various aquatic plants, do not possess the same specific characteristics as floatinghearts. Water lettuce has a rosette form with broad leaves but lacks the distinct leaf stalk structure associated with floatinghearts. Duckweed and giant duckweed, although abundant in Florida's waters, mainly consist of small, free-floating fronds without the defined stalks characteristic of floatinghearts. Thus, floatinghearts stand out in this context due to their unique features and the number of species present in the region.