What Sinkholes and lost rivers may form in regions that have WHAT because groundwater has dissolved the underlying bedrock?

Sinkholes and lost rivers may form in regions that have limestone or other soluble bedrock because groundwater can dissolve these materials over time. This process creates underground voids and caverns; when the surface cannot support its weight, it collapses, leading to sinkholes. Additionally, lost rivers occur when surface water is diverted into these underground channels, often disappearing from sight. These features are characteristic of karst topography, where the landscape is shaped by the dissolution of soluble rocks.