[单项选择]

Humans are forever forgetting that they can’t control nature. Exactly 20 years ago, a Time magazine cover story announced that "scientists are on the verge of being able to predict the tome, place and even the size of earthquakes." The people of quake-ravaged Kobe learned last week how wrong that assertion was.
None of the methods conceived two decades ago has yet to discover a uniform warning signal that preceded all quakes, let alone any sign that would tell whether the coning temblor is mild or a killer. Earthquake formation can be triggered by many factors, says Hiroo Kanamori, a seismologist at the California Institute of Technology, so, finding one all-purpose warning sign is impossible. One reason: Quakes start deep in the earth, so scientists can’t study them directly. If a quake precursor were found, it would still be impossible to warn humans in advance of all dangerous quakes, places like Japan and California are riddled with hundreds, if
A. It is hard to build structures strong enough to withstand serious temblors.
B. Not all structures can be made to withstand the tremor of the earthquakes.
C. The degree of damage caused by earthquakes to different buildings can hardly be predicated accurately.
D. No structures would be strong enough to endure violent earthquakes.

最新试题

• ●    汽车发动机采用复合式润滑，即压力润滑、重力润滑和（）三种润滑方式。
• ●    道德责任制度是提高工作质量的重要手段。
• ●    [单选题]用茶过程中,如果客人面前有热水瓶或电热煮水器,应随时保持这些器具中有 的开水。
• ●    实行对外开放．发展对外经济关系，必须处理好（）。
• ●    在施工图中没有标注尺寸计量单位的，其计量单位应是（）。
• ●    [单选题]北京电影制片厂摄制,凌子风执导的影片( )根据沈从文同名小说改编,讲述了民国初年湘西山区一