A Landfill That Was Abandoned About 20 Years Ago Has

A landfill that was abandoned about 20 years ago has been eroding.Trees and grasses that had grown on the surface have died,the soil is eroding away,and buried wastes are now exposed at the surfaces.Nobody has been doing anything with the landfill for years.Most likely,these problems are the result of

A) rodents trying to dig up the buried wastes.
B) biogas seeping to the surface.
C) settling of the earth as the buried wastes decompose.
D) leachate generation from the buried wastes.