health is to people ( ) sail to boat A .that B.what C.as D.like

这题主要是考查了一个重要的英语固定结构:
A is to B what C is to D.意思是:A对于B来说正如C对于D一样.
所以这题的正确答案是B.意思是:
健康对于人们来说正如帆对于船一样,
这样的句子还有:
Grass is to cow what water is to fish.
Air is to man what water is to fish.