[解析]
(1)推理判断题。根据第一段When the nematodes were placed in room temperature,they began to move.(当线虫被放置在室温下时,它们开始移动。)可知,当把线虫置于室温环境下,他们开始动起来。B.They were still alive when warmed up.(热身时他们还活着。)符合文意,故选B。
(2)推理判断题。根据第二段They can enter a special state called cryptobiosis(隐生现象) ,during which animals reduce their activities and consume very little energy.(它们可以进入一种特殊的状态,称为隐生现象,在此期间,动物减少了它们的活动并且消耗很少的能量。)可知,线虫会进入一种叫做隐生的特殊状态,在这种状态下动物会减少活动消耗极少的能量。故选A。
(3)推理判断题。根据第二段Nematodes can live for years if they're frozen.They can enter a special state called cryptobiosis (隐生现象) ,during which animals reduce their activities and consume very little energy.(如果被冷冻,线虫可以存活数年。它们可以进入一种特殊的状态,称为隐生现象,在此期间,动物减少了它们的活动并且消耗很少的能量。)及第三段They also found the nematodes were able to survive being frozen better if they were dried out a little first.The drying helped them produce a special sugar called trehalose(海藻糖),which helped them survive being frozen.(他们还发现,如果先干燥一点,线虫在冷冻状态下能够更好地存活。干燥有助于他们产生一种名为海藻糖的特殊糖,帮助它们在冰冻中幸存下来。)可知,线虫在隐生状态下会减少能量消耗,它们变干后体内会产生海藻糖来帮助它们存活下来,由此可知线虫的性别和与它们能存活几千年没有因果关系。故选C。
(4)标题归纳题。根据第一段They discovered two tiny round nematodes(线虫) frozen in the sample,which were so small that they could only be seen with a microscope.Tests showed the soil had been frozen for about 46,000 years old.When the nematodes were placed in room temperature,they began to move.(他们发现了两种微小的圆形线虫冷冻在样本中,这些样本太小了,只能用显微镜才能看到。测试表明,这块土地已经被冻了大约4.6万年。当线虫被放置在室温下时,它们开始移动。)及最后一段Most of the nematodes only live a month or two unless they get frozen.(大多数线虫只有一两个月的寿命,除非它们被冷冻。)可知,文章主要阐述了俄罗斯科学家在4.6万年的冻土的中发现了两只线虫,虽然它们正常的寿命只有一两个月,但是当它们被放置在室温下却存活了下来的事情,故文章最佳的标题是D.Short﹣lived nematodes survived for thousands of years.(短命线虫存活了数千年。)故选D。