Exercise : Array declaration syntax

Which of the following choices is the correct syntax for printing an array of integers named a as a comma-separated list of values enclosed in brackets?

1. System.out.println(a.toString());
2. Arrays a2 = new Arrays();
System.out.println(a2.toString(a));
3. Arrays.toString(a);
4. System.out.println(Arrays.toString(a));
5. System.out.println(a);