单项选择题

The phrase "this element of the unknown"(Paragraph 3) refers to ______.

A．the extension of earthquake zones
B．the percentage of earthquake occurrences
C．when and where earthquakes may occur
D．what big damage earthquakes may cause

<上一题目录下一题>

热门试题

单项选择题

Man's research on earthquake forecast at present is to ______.

A．reduce the loss from earthquake disasters
B．lower the frequency of earthquakes
C．release the energy that causes earthquakes
D．analyze the relationship between different earthquakes

单项选择题

Which of the following describes the author's purpose in writing the passage

A．Inform the reader.
B．Entertain the reader.
C．Disprove a concept.
D．Question a concept.