Concept:Inselbergs are isolated residual hills that remain after erosion wears down highlands in dry regions.
Explanation:In desert and semi-desert areas, strong winds and sporadic rain gradually erode the surrounding weaker rocks.
Over time, the softer materials are stripped away, leaving behind the harder, more resistant rock.
These steep-sided, solitary remnants are known as inselbergs.
Seif dunes and barchans are sand dunes, while a volcanic plug forms from cooling magma inside a volcano.
Therefore, the correct option is inselbergs.
Answer:C. Inselbergs