I think a B theorist would say that for those who are witnessing the event, it appears as if it is coming into being and going out of being simply because the observer is “moving” within the time-space block. Think of a Bugs Bunny cartoon (the old style). First, it appears that Bugs Bunny is about to eat a carrot. Then it appears that Bugs Bunny is chewing a carrot. Then it appears that Bugs Bunny has finished eating a carrot. But the reality is that Bugs Bunny is always about to eat a carrot, always chewing a carrot, and always finishing a carrot, because each of those acts are frozen in celluloid (just like blocks of space-time), each just as present as the other. They only appear to be coming into being and going out of being because we are looking at one frame, followed by another, followed by another. It is our movement as observers through space-time that gives Bugs Bunny the appearance of temporal becoming. But this does nothing to change the fact that the frames themselves are causally ordered.

So I think a B-theorist would disagree with RandyE. An effect does not presuppose temporal becoming anymore than Bugs Bunny’s chewing a carrot presupposes temporal becoming. It only presupposes that there is a causal ordering of the eternal “frames,” so that whenever someone views those frames in succession one after another, it gives the illusion of temporal becoming. But after the observer has moved on to another location within space-time, each of those frames remains and are “present” for the next observer who happens to come by (like a time traveler).