Consider the following instance variable and incomplete method.The method sum() should sum up all of the values in array. private double [] array; //assume the array contains values public double sum() { double sum = 0; /* code */ return sum; } Which of the following code segments shown below could be used to replace /* code */ so that sum will work as intended? I. for( int i=0; i-1; i--) sum = sum + array[i]; III. for( int i=0; i