How does the c horizon form?
a) rainwater washed clay and minerals from the a horizon to the c horizon
b) plant roots weather pieces of rock
c) plants add organic material to the soil.
d) bedrock weathers and rock breaks up into soil particles

Technology has affected regional settlement patterns in what ways? choose all that apply. climatic improvement strategies have improved crop productivity. mechanized agricultural methods have improved agricultural productivity. participation in the global economy has increased urbanization. population shifts from urban to rural areas has increased as a result of petroleum production. settlement areas have increased as a result of improved water storage and delivery systems.