The boxes are arranged as follows:
A B C D
E F G H
I J K L
M N O P
The objective is to create a continuous loop by following the arrows. Each box is used only once in the loop. You may pass through boxes. There are at least 16 possible answers to this problem. For example - if ABCD was an answer, then BCDA, CDAB, and DABC would also be accepted.
You may use a ruler of course. Good luck.