I think (b) can be quite useful, for the reason you described. IMO it's useful in physics, as well, because it lets the student reproduce (or at least read about) the experiments that led to our current understanding of the world. For example, are subatomic particles evenly distributed throughout a piece of metal (and, indeed, all matter) ? It's easy enough to answer "no", but it's much more important to discover how the answer was found. Even though this answer itself was pretty far from the truth.