单项选择题

Peter Sturrock thinks that the field of UFO study is in a state of ______.

A．popularization
B．pause
C．development
D．ignorance and confusion
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单项选择题
The scientist from the French space agency did all the following things except ______.
A．taking further photos
B．taking soil samples
C．planting vegetation in the soil
D．taking samples of vegetation
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