What should be the better layout of hardwood floor on my hallway?
I would divide the hallways into 3 areas and keep the areas approximately the same size.  Put the direction of the wood with the longest wall to keep cuts to a minimum.  In my mind this has the middle hallway start (reading left to right) with the angle change and end at the far side of bedroom C.
The change in direction from the hallway to the room would be transitioned at the door ways to make it as inconspicuous as possible.
Bedroom A should be fine.  The hardwood manufacturers typically specify the maximum dimensions and that room doesn't look like it would exceed the standard recommendation but check the install specifications.