Over the past decades, forest area in China as a result of massive deforestation.
A. had decreased
B. decreased
C. is decreasing
D. has been decreasing
网友回答
A. had decreased
B. decreased
C. is decreasing
(答案→)D. has been decreasing
解析： 考查时态。Over the past+时间段，用现在完成时态，故选D。