【正确答案】 A

【答案解析】what可以作连词用，引导方式状语从句，例如：The people is to the people’s armywhat water to fish．人民的军队离不开人民，就像鱼离不开水一样。A molecule is to a chemical compound what an atom is to an element．分子对于化合物，就像原子对于元素一样。Leaves do for plants what lungs do for animals．叶子对于植物的作用，正如肺对于动物的作用一样。The blueprint is to the builder what the outline is to the writer．蓝图对于建筑师就像提纲对于作家一样。