Questions 17 to 20 are based on the following passage. At the end of the passage, you will be given 20 seconds to answer the questions.
Now listen to the passage.
What can we infer from the talk
A．Powerful earthquakes usually occur after minor ones.
B．Modern facilities add to the danger of an earthquake.
C．Passing trucks are as dangerous as minor earthquakes.
D．There is a powerful earthquake occurring every two years.
参考答案：B
解析：[试题分析] 事实推断题。
[详细解答] 本题答案可以从。Instead, many deaths and injuries in earthquakes result from falling objects and the collapse of buildings, bridges, and other structures. Fire resulting from broken gas or power lines is another major danger during an earthquake. Spills of dangerous chemicals are also a concern during an earthquake中推断出来。