Karst topography is formed when the underground water breaks down the bedrock into soluble rocks. Hence, the bedrock of Karst topography is made of soluble rocks such as limestone. There is no surface water and topsoil in this topography and hence, the water from rains become part of the groundwater.
The answer is D. Because planting nonnative species is bad for the area because the plants that normally grow there have to compete with that new species then.
