I was too lazy to draw another one from scratch, so I've just photoshopped it. Or more precisely, paint-dot-netted it. ;)
Anyway, the difference here is that the floor isn't entirely covered by glass. You have stripes on the floor that can be used to make the floor more detailed. Of course you also see the stripes in concept A, but there they're under the glass and therefore some of the details of the texture aren't visible, as the glass texture isn't 100% transparent (due to dirt or something).