Final answer:
Swamps, channels, floodplains, and submarine slopes all play a role in the development of karst landscapes.
Step-by-step explanation:
The correct answer is A: Karst landscapes. Swamps, channels, floodplains, and submarine slopes all play a role in the development of karst landscapes. Karst landscapes are characterized by features such as caves, sinkholes, and underground drainage systems, all of which are formed by the dissolution of soluble rocks, such as limestone or dolomite, by water.