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