Well first of all, without having to understand anything about the question you can work it out just with common sense.
It's not the first answer because you can't prove a theory that's about the past, same with evolution aswell. You can only gather evidence that supports it.
So it can only be the 2nd or 3rd answer.
Well it can't be the 3rd answer because (same reason as the first and also) theres not enough known about the universe to make a statement like that about the future.
So it can only be the 2nd answer.
But ye the question is about redshift. Basically everything is moving away from the center of the universe, including waves from the electromagnetic spectrum (light), and because we're moving further away it stretches the wave so that it moves to the 'red' side of the electromagnetic spectrum.
Its the same with sound waves when a car drives past you. When a formula 1 car is moving towards you it will sound very high pitched because the waves get compressed. But when it drives passed you it sounds lower pitched because the waves are getting stretched by the car moving away. (think of it like a slinky attatched to the car, but the slinky is trying to get towards you in both instances
).
So in the case of the universe, earth is moving away from the center of the universe. And we can say that because of the stretched microwaves. If we were moving towards the center of the universe it would be blue shift and we'd be detecting gamma rays instead (or stuff on that side of the spectrum).
edit: lol my bad I was looking at 8a)ii) , the question is still about blue and red shift anyway though.