What will be the output when you add String object in HashSet?

Problem statement: Given code is 

1. public class Test {
2. public static void main(String[] args) {
3. HashSet<String> s = new HashSet<>();
4. s.add("A");
5. s.add("B");
6. s.add("C");
7. s.add("A");
8.   System.out.println("Elements: \n" + s);
9.   System.out.println("Size: " + s.size());
10.   System.out.println("Objects: " + s);
11. }
12. }

Answer:
Elements: 
[A, B, C]
Size: 3
Objects: [A, B, C]