Answer: 1 The correct answer is that CMB radiation was spread uniformly throughout the whole universe.This was related to big band theory because this theory predicts that the universe was a very hot place and as it cooled down it should have been filled with laterally the remnant heat over from the Big Bang called as cosmic microwave background.
Answer: 2 CMB radiation was discovered accidentally when Penzias and Wilson were performing some experiment and they noticed a ' hum' noise that was constantly detected by the antenna even after removing all the disturbing sources.
Then it was realized that it is cosmic microwave background radiation.