[解析]
(1)B.细节理解题.根据文章第二段,According to the results,elephants have 38 additional modified copies of a gene that encodes p53,a well﹣defined tumor suppressor(肿瘤抑制基因),as compared to humans,who have only two.根据研究结果,与只有两个基因的人类相比,大象还有38个额外的,可调整拷贝的基因,这个基因编码为p53,一种定义明确的肿瘤抑制因子.可知,大象和人类相比不太可能得癌症主要因为大象有更多的P53基因,它可以抑制并破坏癌细胞.结合选项,故选B.
(2)C.词义猜测题.根据文章第二段,According to the results,elephants have 38 additional modified copies of a gene that encodes p53,a definite tumor suppressor,as compared to humans,who have only two.根据研究结果,与只有两个基因的人类相比,大象还有38个额外的,可调整拷贝的基因,这个基因编码为p53,一种定义明确的肿瘤抑制因子.可知,划线单词意为:抑制剂,A.multiplier乘数;B.complex复杂;C.restrainer抑制剂;D.coordinator协调员,结合选项,故选C.
(3)A.观点态度题.根据文章第四段,But Prof Mel Greaves,from the Institute of Cancer Research in London,says we should focus on why humans have such high levels of cancer.但是来自伦敦癌症研究所的梅尔•格雷夫斯教授说,我们应该关注为什么人类的癌症水平如此之高.可知,Mel Greaves教授对于这项研究的态度是怀疑的.A.Doubtful怀疑的;B.Neutral中立的;C.Critical批评的;D.Favorable 有利的,结合选项,故选A.
(4)D.推理判断题.根据文章最后一段,Because they have 100 times as many cells as people,they should be 100 times more likely to have a cell slip into a cancerous state and cause the disease over their long life span of 50 to 70 years.因为它们的细胞数量是人类的100倍,所以细胞滑入癌变状态并在其50到70年的长寿期内引发疾病的可能性应该是人类的100倍.可知,人们原以为大象会更容易得癌症.结合选项,故选D.