What would be the equivalent pointer expression for referring the array…

Correct expression: *(*(*(ar + m) + n) + o)

Why this is correct:

1. ar + m points to the m-th 2D subarray; applying * gives ar[m].

2. *(ar + m) + n points to the n-th 1D subarray inside ar[m]; applying * to that gives ar[m][n].

3. *(*(ar + m) + n) + o points to the o-th element of that 1D array; the final * returns ar[m][n][o].

Why the other given expressions are wrong:

• Expressions that add m and n at the same pointer level (e.g., *((*(ar) + m + n) + o)) combine indices and end up addressing ar[m + n][...] rather than ar[m][n][...].

• Forms that place + o outside the final dereference or omit the final * produce an integer plus o instead of indexing into the innermost array; they therefore fail to return ar[m][n][o].

• Any expression that misses one level of dereference or combines levels of pointer arithmetic does not reflect the nested structure of a three-dimensional array and so is incorrect.