The opinion of many engineers is that the architects that designed the New York World Trade Center Twin Towers did a good job in

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问题     The opinion of many engineers is that the architects that designed the New York World Trade Center Twin Towers did a good job in designing the buildings. The buildings were safe from the hazards envisioned at the time. Indeed, they were designed to withstand the force of aircraft that might crash into them. They were not, however, designed to withstand the effects of the very high temperatures generated by the ignition of tons of aviation fuel carried by the aircraft.
    Steel lightly covered with concrete is the main structural component of the towers and steel loses a lot of structural strength when heated to 1,100 degrees Centigrade and beyond, as it was. To shield the steel the towers beams were coated with a few centimeters of concrete. That insulation was to provide structural integrity for at least 1 hour of fire. The towers met that test. The south tower lasted 62 minutes. The north, 103 minutes. Tragedy followed when not all could escape prior to the collapse.
    Most experts agree that the Twin Towers were very well-designed. Many also agree that the people planning the attacks were very knowledgeable and aimed the aircraft at a height that would effect the most damage. The aircraft crash and the resulting fuel fed fires were aimed at about the 90th floor. That was just high enough to insure that the upper floors would weaken with the heat and crack down, dropping into the remaining part of the building.
    The mass of the falling top floors created such a falling load that some experts estimate it exceeded by 5 to 10 times normal bearing loads. The effect was like a giant hammer, each floor contributing more weight to be born by the next floor down.
    Were the Trade Towers well designed? Engineers say yes. But the public believes that architects will never again design a tall building without considering the effects of terrorist attacks of all potential kinds. That not only includes the ability of the structure to withstand attack but the means to allow the buildings occupants to escape in time to survive.
According to the passage, those who designed the towers could have done better if______.

选项 A、the towers may withstand the force of aircraft
B、the engineers take the effects of the very high temperatures on the structure into consideration
C、the towers held stable until all of the people inside managed to escape
D、the collapse of the towers may be avoided

答案B

解析 本题推理题。根据文章第一段第4句“They were not…by the aircraft.”,可以推出:设计双子楼的工程师们如果更多地考虑到高温的影响并作出相应的调整的话,结果会好一些。
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