In zones where earthquakes are known to occur, construction techniques can significantly reduce the effects of seismic wave.
A. to improve
B. improving
C. improved
D. being improving
网友回答
A. to improve
B. improving
(答案→)C. improved
D. being improving
解析：考查非谓语动词。此处improved 作construction techniques的定语，建造技巧和提高之间是被动关系。
句意为在一些地震频发的地区，改良的建造技巧可以显著地嫌少地震的影响、