Of all the controversial topics on these forums this is the easiest.
Clearly B
I may as well just lock this now... 
A. (closest to wall)
Just looks neater
if kids spin the roll it does not reel off all over the floor
(Nebbs I wanna know - what the hell did they do before 1857? 
In the bush in 2000BC, pretty obvious but early 1800's is pretty civilised so I am wondering that's all....)
B.
Reason: You can more easily see the perforation when tearing off a length hence have more accurate control of the tear.
^^ You can still unroll it to the floor if its option 'B', you just don't need to go fishing for the end first.
And I'm one of those 20% that flip it around if it been put on the roll backwards. I'm not afraid to admit it
I think the Master Debaters would be the most experienced people to advise on this one
