Why is water scarcity increasing on earth?
a. the polar caps are melting.
b. global population is decreasing.
c. the amount of freshwater on earth is decreasing.
d. more land is being farmed.

17. the soil erosion pictured here is the result of what? a. harvesting renewable resources at a rate greater than the sustainable yield b. a mudslide caused by excessive rains c. harvesting renewable resources at a rate lower than the sustainable yield d. the transition between geologic eras and eons