SCJP Questions

Given:
1 class super {
2 public float getNum() {return 3.0f;}
3 )
4
5 public class Sub extends Super {
6
7 )
Which method, placed at line 6, will cause a compiler error?
A. Public float getNum() {return 4.0f; }
B. Public void getNum () { }
C. Public void getNum (double d) { }
D. Public double getNum (float d) {retrun 4.0f; }
Answer: B