What is the output for the below code?

public class Test{
      int _$;
      int $7;
      int do;

      public static void main(String argv[]){
            Test test = new Test();
            test.$7=7;
            test.do=9;
            System.out.println(test.$7);
            System.out.println(test.do);
            System.out.println(test._$);
      }
}

A. 7 9 0

B. 7 0 0

C. Compile error - $7 is not valid identifier.

D. Compile error - do is not valid identifier.

E. None of these

Answer: Option D

Solution(By Examveda Team)

$7 is valid identifier. Identifiers must start with a letter, a currency character ($), or underscore ( _ ). Identifiers cannot start with a number. You can't use a Java keyword as an identifier. do is a Java keyword.