The past two years a sharp rise in oil price, which adds to the burden of auto transportation industry.
A. witnessed
B. has witnessed
C. is witnessing
D. witnesses
网友回答
A. witnessed
(答案→)B. has witnessed
C. is witnessing
D. witnesses
解析：考查时态题。根据the past two years可知应该用现在完成时。本句是无生命的东西作主语，此处的the past two years作主语。witness 解释为：见证了。