supernovas the big bang collisions of galaxies modern decay of unstable atoms
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Astronomers have found low-energy background radiation in every part of the sky that they have studied. This radiation is taken as evidence of energy remaining from which event?
Possibilities:
- supernovas
- the big bang
- collisions of galaxies
- modern decay of unstable atoms

the big bang