单项选择题

Seriously-deformed zones appear ______.

A．whenever the crusts move over mantle
B．when the plates move towards each other
C．in the narrow boundaries where two plates meet
D．to be the major topographical feature of the Earth

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热门试题

单项选择题

This passage is probably ______.

A．a newspaper advertisement
B．a chapter of a novel
C．an excerpt from a textbook
D．a scientific report of new findings