Why pleasant smells do not reduce pain in man is a question still by scientistsA
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Why pleasant smells do not reduce pain in man is a question still _______ by scientists
A.answered
B.being answered
C.to be answered
D.that answered
试题答案
C
考查非谓语动词。句意：为什么令人愉快的气味不能降低人的痛苦仍是科学家要回答的问题。根据语境看问题还没被解决所以用不定式的被动式做a question的定语。