Final answer:
Rain and wind erosion caused the changes in the landscape of the cave.
Step-by-step explanation:
The best explanation for the changes made to the landscape of the cave is rain and wind erosion. Over the course of 25 years, rainfall and wind can gradually erode the rocks, making the tips less pointed and rounding the overhang above the entrance. This erosion is caused by the natural elements of rain and wind, which slowly wear away at the rock formations.
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