i think everyone (including the setter) is missing the point with the water question - it has nothing to do with water. forget the water!

there is a vital difference between "therefore we can predict that every future examination will reveal etc." and "therefore every future examination will reveal etc." (the latter being what the revealed answer addresses)

the question in fact asks whether prediction is possible. now there is nothing to stop us predicting anything about anything. but there is nothing in conditions A) and B) which leads to the logical conclusion that this should be so.

therefore the logical answer is that the statement is invalid