I would say they are all expressions a native speaker might use, in the sense that none of them is grammatically incorrect or wrong in its use of words. But it's difficult to think of a context in which A2 would be used. One would normally talk of having an IV drip rather than getting one. (One might say that a nurse would GET the equipment ready for a doctor or senior nurse to GIVE or ADMINISTER the treatment.) We would tend to say he was given an IV drip, not he got an IV drip. B7 would also, I think, be comparatively rare, but it's tenable to think of a doctor saying something like, 'You don't need surgery: I can treat your condition with a course of injections.'