此题初衷是exit airplanes swiftly after accidents, since gases released following accidents are toxic to humans and often explode soon after being released。A中说增加了leave的时间,和exit airplanes swiftly after accidents违背,即有explode soon的危险。而c中之时说hoods没有防止igniting.但有protect passengers from the toxic gases的能力,毕竟比原来好了,说明应该实行safety officials' recommendation。并不是拒绝safety officials' recommendation的原因。是这样理解吗?
我觉得C里的"do nothing to prevent the gases frome igniting"完全就没用,原文那个定语从句说得很清楚:smoke hoods that prevent inhalation of the gases.为了prevent inhalation于是用hook,不是为了别的,所以只要能prevent inhalation就行。如果按照C的思路对的话,那如果改成:hook能protect passengers from the toxic gases,但不能preventgases release那就也行了~ 所以,只要能达到原文的目的就行,其他辅助作用时候有,比如是否好看,是否能听音乐等等多功能完全就不需要考虑