Respuesta :
Answer:
Actually its D.Doppler effect
Explanation:
Because they never mentioned anything about the heliocentric theory and the geocentric theory and the big bang theory is about how they thought the universe was before the big bang happend so that leaves you with the doppler effect.
I never explain my answers so you should believe me
Also i go to k-12 and it says thats the answer
Answer: D: Doppler Effect
Explanation: 6.02 Quiz: Origin of the Universe