单选题 Boil drinking water for at least five minutes, to kill the germs, then let it cool in a clean container. Keep it covered.
【正确答案】 C
【答案解析】germ“微生物、细菌”；bacterium“细菌”；insect“昆虫”；bug“虫子，臭虫”；pest“害虫”。句意：饮用水至少要煮开5分钟，把细菌杀死，然后在容器中凉凉，盖好。