An area with caves and sinkholes is known as which landscape feature?

• A. Mountain Range
• B. Desert Basin
• C. Karst Topography
• D. Floodplain

Answer: (D)

Karst topography is the landscape formed in areas where soluble rocks, like limestone, are dissolved by slightly acidic water. Rainwater absorbs carbon dioxide and becomes a weak carbonic acid that slowly dissolves the rock, carving out caves and underground drainage. Over time, some of these underground voids collapse, creating surface depressions called sinkholes. That combination of caves and sinkholes is characteristic of karst landscapes, along with features such as underground rivers and distinctive rocky towers formed by differential dissolution. The other options describe different landforms: a mountain range forms from tectonic uplift and folding, a desert basin is an arid low-lying area, and a floodplain is a river-adjacent plain built up by sediment during floods.