Which of the Following Is Not a Possible Solution to the Fermi

Multiple Choice

Which of the following is not a possible solution to the Fermi Paradox?

A) We are the only intelligent civilization to have ever arisen in the Milky Way.
B) There is a galactic civilization, but it is being actively hidden from us.
C) There is a galactic civilization, but we are currently unable to detect or recognize it.
D) Given the current age of our galaxy, there has not been enough time for a galactic civilization to develop.
E) Of all of the intelligent civilizations in the Milky Way, none has chosen to create a galactic civilization.