Which of the following does not declare a 2-by-2 array and set all four of its elements to 0?
1) int[][] arr = new int[2][2];
2) int[][] arr = {{0, 0}, {0, 0}};
3) int[][] arr = new int[2][2]{{0, 0}, {0, 0}};
4) All of these initialize all four of the array elements to 0.