The climate was once colder. The shells were carried by the wind. The mountain was covered by water. The shells once lived on dry land.
I gave my students this multiple choice question: A scientist found fossils of ocean shells on a mountain top. Based on this find, which statement can be made?

Only one answer is correct among these 4 choices:
- The climate was once colder.
- The shells were carried by the wind.
- The mountain was covered by water.
- The shells once lived on dry land.

Could you tell me which one is correct?

The mountain was covered by water.