What is the output of following program?abstract class Sum{ public abstract int sumOfTwo(int n1, int n2); public abstract int sumOfThree(int n1, int n2, int n3); public void disp( ){ System.out.println("Method of class Sum"); }}class DemoAbstract1 extends Sum{ public int sumOfTwo(int num1, int num2) { return num1+num2; } public int sumOfThree(int num1, int num2, int num3) { return num1+num2+num3; } public static void main(String args[ ]){ Sum obj = new DemoAbstract1( ); System.out.println(obj.sumOfTwo(3, 7)); System.out.println(obj.sumOfThree(4, 3, 19)); obj.disp( ); }}

• A. 1026Method of class Sum
• B. 2610Method of class Sum
• C. Method of class Sum2610
• D. Error