C and E were easily eliminated for me first because of their reference to the modern world more so than from the concept of ranking, just because Barbu acknowledges Greek civilization but mentions nothing about the modern west

I'm confused a bit because I assumed the tunnel was submerged underwater, but not the cave. Thus chose A under the assumption that higher water levels had existed and caused dripping on the cave floor. Could anyone clarify how I could have read the question differently and correctly identified the complete submerging of both the cave and the tunnel?