Hey there,
Based on my research, your correct answer would be "Beaches change over time as waves move further up the shore." It would be your correct answer because as the waves move the water, the waves will slowly move up the shore. Have you ever been in the beach before? If you have, if you stand right at the end of the beach, you would feel how the water kind of pushes you. So this is what the water does to the shore.
~Jurgen