To most of us, nuclear is an all-or-nothing word. Nuclear war is unthinkable. Nuclear weapons must never be used. Nuclear power

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问题     To most of us, nuclear is an all-or-nothing word. Nuclear war is unthinkable. Nuclear weapons must never be used. Nuclear power plants must be perfectly safe. Nuclear meltdown is the end of the world. "Going nuclear" means you’ve hit the fatal button, and there’s no turning back.
    Two days ago, I saluted the reactor containment vessels at the Fukushima Daiichi power plant for surviving the earthquake and tsunami. "Everything that could go wrong did", I wrote. Hours later, an explosion damaged one of the containers. That was a corollary to Murphy’s Law: Anyone who says "Everything that could go wrong did" is overlooking something else that could go wrong.
    The nuclear industry likes to think failure isn’t an option. It builds power plants according to a principle called "defense in depth." Under this principle, as articulated by the Nuclear Energy Agency, "consecutive and independent levels of protection ... would all have to fail" before harm could happen. But the levels of protection at Fukushima weren’t really independent. They were all taken out by the same chain of events. The quake triggered the tsunami, knocking out the diesel generators. The cooling system’s power failure led to explosions that knocked out the cooling system’s conduits. The overheated reactors produced hydrogen explosions that blew off the roofs of the reactor buildings, exposing spent-fuel pools to the atmosphere.
    Nothing is more exasperating than reading reports about all the things that can’t be done at Fukushima—fixing valves, pumping water, ascertaining damage—because of heat, radiation, or the risk of explosion. Last year, BP plugged an oil leak a mile under the Gulf of Mexico with the aid of remotely operated vehicles. Why doesn’t Japan, the world’s most robotically advanced country, have unmanned vehicles on hand to do simple but dangerous jobs at a radiation-contaminated nuclear power plant? Ten minutes ago, I got a newsletter from the unmanned-vehicles industry about all the cool things robots are doing to help Japan. It has not a word about the nuclear reactors. That’s disgraceful.
    To head off the next nuclear accident, we need to think the parameters of plant design. Why do we build backup cooling pumps for reactors but not for spent-fuel spots? And we need layers of protection that are truly independent. If some safety mechanisms require electricity, others should be functional without it. Store cooling water above the reactor so you can deliver it with plain old gravity if you lose power. And diversify the layers. At Fukushima, all the gizmos failed, but the containers have largely held firm. Build in different kinds of protection—barriers, gizmos, training, manual tools—so that if one kind fails, another can intercede.
    If everything goes wrong, and your reactor melts down, don’t give up. You still have evacuation and iodine. And even if Fukushima becomes another Chernobyl, nuclear energy still has a much better safety record than fossil fuels, just as stocks have a better track record than bonds over the long term, despite the occasional crash. But that safety record depends on us. We have to learn from Fukushima. We have to give ourselves a fighting chance when things go wrong, as they sometimes will. Fukushima’s workers haven’t surrendered. We shouldn’t either.
The underlined word "unmanned"(Para. 4)is NOT RELATED in meaning to______.

选项 A、robotic
B、inhumane
C、pilotless
D、driverless

答案B

解析 属词义题。“unmanned”意为“无人操作或控制的”。选项A“robotic”意为“机器人控制的”,选项C和选项D的“pilotless”和“driverless”均有“无人驾驶”的意思,它们都与“unmanned”是近义词。选项B的意思是“不人道的”,故选项B为正确答案。
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