Answer:
The main reason why the magnetic field lines do not cross each other is because of the resultant force (the single force) on a north or south pole at any one point on earth can only be in one direction...
Step-by-step explanation:
This means that if you were to have a compass it needle cannot be showing two different directions. THIS MEANS THAT THE MAGNETIC FORCES ACTING FROM POLE TO POLE ACTS ONLY IN ONE DIRECTION, NOT 2
HEY, HOPE THIS HELPS!!