A. to help to destroy old cells and boost new ones. B. to alter the natural process known as apoptosis. C. to compare different levels of proteins. D. to find out ways to protect aging brain cells. 参考答案:D 答案解析:[题解] 根据提问,先找到关于研究目的的段落:That prompted researchers to look at whether cutting calories might also play
第30题:[单选题]A型人格特质的主要成分不包括( )。 A. 有更强的竞争性 B. 更容易产生愤怒和敌意 C. 有更强的紧迫感 D. 更容易随遇而安 参考答案:D A型人格特质的三个主要成分:有更强的获取成就的竞争性;更强的时间紧迫感 ;对挫折情境更容易产生愤怒和敌意。