I think me adding more details will clear things up.
The setup presupposes a certain amount of realism. Start with Possible Worlds Semantics, where logical propositions are attached to / refer to the set of possible worlds in which they are true. A hypothesis is some proposition. We think of data as getting some proposition (in practice this is shaped by the methods/tools you have to look at and measure the world), which narrows down the allowable possible worlds consistent with the data.
Now is the part that I think addresses what you were getting at. I don't think there's a direct analog in my setup to your (a). You could consider the hypothesis/proposition, "the set of all worlds compatible with the data I have right now", but that's not quite the same. I have more thoughts, but first, do you still want feel like you idea is relevant to the setup I've described?
In light of reading through Raemon's shortform feed, I'm making my own. Here will be smaller ideas that are on my mind.