He proposed the theory of Continental Drift. He believed that all of the continents were once joined together in a super continent he called Pangea (not sure if that's spelled right I studied this awhile ago). He proved this by showing similarities in fossils in completely different continents and showing how well the continents could fit together.
The appropriate answer is c. geysers. A geysers a hot water fountain that spouts intermittently with great force, frequently accompanied by a thunderous roar. The world famous Old Faithful is located in Yellowstone National Park. This geyser erupts every 65 min sending a jet of water almost 60 meters into the air. Sinkholes and caves are formed by the action of groundwater on carbonate rocks which causes them to colapse and former these structures.
The answer is C hope this helps <span />
