往OuterClass类的代码段中插入内部类声明, 哪一个是错误的:public class OuterClass{    private float f=1.0f;    //插入代码到这里}

• A.class InnerClass{public static float func(){return f;}}

• B.abstract class InnerClass{public abstract float func(){}}

• C.static class InnerClass{protected static float func(){return f;}}

• D.public class InnerClass{ static float func(){return f;}}