【正确答案】 C

【答案解析】[解析] 23-25 Word comes from California of a new weapon in the war on household pests. Two scientists working for a firm in Annahine, California developed a new method to eliminate insects without using dangerous chemicals. The new poison: hot air. The basic idea is that insect pests can not adjust to temperatures much above normal. In laboratory experiments, cockroaches and termites can't survive much more than a quarter of an hour at 100 degrees Fahrenheit or about fifty degrees Centigrade. The new method involves covering a house with a huge tent, and filling it with air heated to around 65 degrees Centigrade. Hot air is forced in with fans and the tent keeps the heat inside the house. Since termites must be continued for four to six hours. But when it's all over and the insects are dead, there is no toxic residues to endanger humans or pets, and no funny smells. Scientists claim that there's no danger of fire either. Since very few household materials will burn at 65 degrees Centigrade. In fact, wood is prepared for construction use by drying in the ovens at 80 degrees Centigrade, which is substantially hotter. 23. What makes the new system better than other treatments? 问，新的杀虫方式比其他方法的优越之处在哪儿?短文开始就提到，两位科学家发明了一种新的除虫方式，可以不用危险的化学元素，dangerous的反义词为safe，所以正确答案是C，而这一点在下文中也有进一步的说明。

【正确答案】 A

【答案解析】[解析] Why are the houses covered with tents? 问，为什么要用帐篷将房子罩起来?文中提到，这种新的除虫方法要用一个巨大的帐篷把房子罩起来，用风扇将高温的空气吹进去，帐篷将热量保持在房子里。所以正确答案是A。

【正确答案】 C

【答案解析】[解析] Why does the announcer mention that construction wood is dried by heat? 问，为什么要提到建筑用的木头是用火烤于的?在短文最后一句提到，木头在被用作建筑用木之前是在炉灶中用80℃的高温烘烤的，除虫时所用热空气的65℃比这个温度要低得多，所以这种除虫方法对建筑房子中的木头也没有什么危害。由此可见正确答案是C。