It was once underwater. It was once much warmer. It has become a rockier place. It has changed little from then.
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Fossils of sea animals were found in a cave in Arkansas. What does this mean about that area of Arkansas in the past?
Possibilities:
- It was once underwater.
- It was once much warmer.
- It has become a rockier place.
- It has changed little from then.

It was once underwater.