With the help of high technology, many new substances（物質(zhì)）______in the past years.
A．discoveredB．have discoveredC．had been discoveredD．have been discovered
D
考查時態(tài)語態(tài)：時間是in the past years.時態(tài)用現(xiàn)在完成時，new substances和discover是被動關系，句意是：隨著高科技的發(fā)展，在過去的這些年里，很多新的物質(zhì)被發(fā)現(xiàn)了。選D。
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