单选题
It is also important to have something that can clean water and kill______so water from other sources can be made safe to drink.
【正确答案】
B
【答案解析】解析：句子大意为：还有一件很重要的事就是，要有东西可以净化水源、杀灭细菌，以便从其他来源弄来的水可供安全饮用。A项plasmodia“疟原虫”，B项bacteria“细菌”，C项criteria“标准”，D项malaria“疟疾”。所以答案为B项。