Silicon is not used for genuine electronic paper because ______.
A. it is used in the semiconductor in the transistors
B. it is all right for applications such as posters
C. it is brittle and costly
D. cheap and flexible electronic components are needed
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How many institutes or organizations are involved in the paper published in the Proceedings of the National Academy of Sciences？
A. 2.
B. 3.
C. 4.
D. 5.
According to Vesselin Bontchev the notion of "good" viruses is ______.
A. just like a novel
B. something new
C. something usual
D. something unique
Judging from the context, VBS.Noped.A@mm is probably ______.
A. a good thing
B. an unknown virus
C. a dangerous virus
D. a benign virus
It is implied by the author that the magazines are ______.
A. sheer art and slogans
B. full of lure and deception
C. dream of perfect beauty for women
D. useless cream, tablets and pills
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