I don't understand why changing order will casue the result

(a) For each of the following alternate orders of the branches, indicate one of the following: (A) The function would still be correct. (B) The function would still type-check (no unreachable branch) but would no longer be correct. (C) The function would no longer type-check (due to an unreachable branch). i. line 2 ; then line 1 ; then line 3 ii. line 3 ; then line 1 ; then line 2 iii. line 3 ; then line 2 ; then line 1 iv. line 1 ; then line 3 ; then line 2