Answer:
D.The universe is expanding.
Explanation:
The cosmic microwave background is thought to be leftover radiation from the Big Bang, or the time when the universe began. (The universe is still expanding today, and the expansion rate appears different depending on where you look). The CMB represents the heat left over from the Big Bang.
Answer:
D.The universe is expanding.
Explanation:
The expansion of the universe is the increase in distance between any two given gravitation-ally unbound parts of the observable universe with time.
