Laying claim to DNA stretches can be careless genetics because ______.
A. those who patent gene fragments are not qualified geneticists
B. the same gene fragments are often patented by different scientists
C. geneticists have no idea what they are going to do with patented genes
D. some of the gene fragments patented contain no real genetic information
不可抗力发生后，承包人应在力所能及的条件下迅速采取措施，尽可能减少损失，并在不可抗力事件发生过程中，每隔( )向工程师报告一次受害情况。
A. 4d
B. 5d
C. 7d
D. 8d
The author's main purpose in writing this passage is to ______.
A. discuss the negative effects of patenting genes
B. face possible moral consequences of patenting genes
C. condemn the selfishness of researchers who patent genes
D. weigh the advantages and disadvantages of patenting genes
滑参数停机的主要目的是（ ）。
A. 利用锅炉的余热发电
B. 均匀降低参数增加机组寿命
C. 防止汽轮机超速
D. 降低汽轮机缸体温度，利于提前检查
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