单选题：What can scientists do now?

题目内容：

What can scientists do now? A．Prescreen a baby's se
B．Screen babies for desirable attribute
C．Insert genes that parents wan
D．Craft genes in a la

参考答案：

答案解析：

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请选择（10）处的最佳答案．A．later B．latter C．lately D．afterwards

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Death Control　　A very important world problem -- in fact, I am inclined to say

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