若类A和类B的定义如下:class A{int i,j;public:void get();//...};class
B: A{int k;public:void make(int );//...};void
B::make(int j){k = i*j;}则上述定义中,非法的表达式是( )
A:void get();
B:int k;
C:void make(int )
D:k=i*j;