With the help of high technology more and more new substances in the past years.A. disc

问题补充：

With the help of high technology, more and more new substances in the past years.

A. discovered

B. have discovered

C. had been discovered

D. have been discovered

答案：

A. discovered

B. have discovered

C. had been discovered

(答案→)D. have been discovered

解析：时态和语态。由句中的时间状语in the past years可知，空格应填现在完成时；又因句子中的主语new substances与discover为被动关系，故选D项。