Which of the Following Is Not Considered a Potential Solution

Multiple Choice

Which of the following is not considered a potential solution to the question of why we lack any evidence of a galactic civilization?

A) The galactic civilization is deliberately avoiding contact with us.
B) There is no galactic civilization because we are the first species ever to achieve the ability to study the universe.
C) There is no galactic civilization because all civilizations destroy themselves before they achieve the ability to colonize the galaxy.
D) The galactic civilization probably is undetectable because they operate under different laws of physics from the ones we know.