答案：A

题目分析：这是由介词+which引导的一个定语从句，介词的选用要与先行词的匹配，先行词作介词的宾语。句意，鱼儿不能从水中拿出来，没有水，他们很快就会死。故选A

点评：介词+which/whom引导定语从句时，介词选择要根据从句的动词来定eg: I don't know the person with whom you talked just now. 此处从句为  talk with sb. 和某人交谈。用talk with.当先行词是物的时候用which是，也是考虑从句动词与先行词的搭配eg. could you find the bus by which you get here.