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

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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。