Which of the following is the ultimate reason for the decline of tropical rain forests

A．it is nature itself that should take the blame for the decline of North Africa
B．climatic changes coupled with forest abuse result in the decrease of forests in North Africa
C．without sufficient forests, the rains will take away all the organic nitrogen
D．since Roman times the rain forests in North Africa has been decreasing gradually

A．the first publication of Joyce Carol Oates
B．the realistic description of her own experience
C．published when Oates worked as an instructor in the University of Detroit
D．totally derived from her own imagination