I’m really confused with this question. The correct answer is (D) but I chose (E).
So here, “;” indicates support and “not even” means that this is an extreme case.
I thought the sentence meant “it’s not just fiction but this phenomenon is actually impossible” and hence I chose (E).
But the way Greg guessed it was “not mere fiction” = real. Since this is an extreme case, “not even rare”. How is rare an extreme word for real?