There isn't really a "correct" one as such, any of those would be fine. The main thing you have to be careful of is the backing, flat sawn (as in 2 & 3) is fine if the grain is near perfect, ie. you have a single growth ring running the full length of the bow, but if that's not the case you're safer with bias grain or quartersawn (1 & 4), but you still need to have a minimal amount of run-off. In essence the grain orientation of the core and belly is not something you need to worry about a great deal.