1. What kind of erosion has helped paleontologists and geologists study the rock layers in the Badlands National Park? A. The mechanical forces of wind, water and freezing wore away the layers of rock.

B. Chemical erosion causing hydration causing rocks to break up and ways away.

C. A combination of chemical and biological erosion wore away layers of rock.

D. Biological weathering from lichen and bacteria colonies ate away at the rock layers.