What is the authors attitude towards enhancement evolution？
A. Skeptical.
B. Impartial.
C. Supportive.
D. Biased.
We can infer from the fourth paragraph that______.
A. enhancement evolution is technically impossible
B. parents have the final say on children"s genome change
C. parents and children usually have different designs for the future
D. enhancement evolution may cause moral problems
The word "vulnerable"(Line 6, Paragraph 2)most probably means______.
A. entirely wiped out
B. on the alert
C. easy to be attacked
D. getting immune
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