Karst topography is a landscape or landform created when nearby groundwater or surface water dissolves rocks. Examples of karst topography include caves and sinkholes, as shown in the images. (groundwater is water founded in cracks and soil, sand, and rock) Based on your experimental results, what can you conclude about the type of rocks that once existed in these locations and the acidity of the nearby groundwater?

What I got so far is: "I can conclude about the type of rocks once existing in these locations that they are most likely limestone rocks."