We can study how galaxies evolve because the farther away we look, the further back in time we see.
Answer: Option D
Explanation:
As the galaxies are located far away from us and also as per the broad band theory, these galaxies are spreading as the time goes. So as time passes, the galaxies are moving further light years away.
So depending upon the time taken for the light waves to reach Earth from these galaxies will state the time they have evolved. So the farther or more lately the light reaches the earth surface, the further time back we can see its evolution. Thus option d is correct choice.
