【题目】Los Angeles Times reported that researchers may have found a way to ______ human life by changing certain genes, so that humans might expect to live twice as long.
A. extend B. preserve
C. multiply D. transform
在线课程【答案】A
【解析】A 延长；B保存；保护；维持；C乘；使增加；使繁殖；D改变，使…变形，转换。句意：《洛杉矶时报》报道研究者或许已经找到了一种延长人类寿命的方法。故选A。