Dinosaur footprints were found near the Grand Canyon. Fish were found living in the rivers of the Grand Canyon. Fossils of ocean animals were found at the Grand Canyon. Bones from desert animals were found at the Grand Canyon.
I gave my students this multiple choice question: Scientists claim that the area around the Grand Canyon was once covered by an ocean. What evidence would support their claim?

Only one answer is correct among these 4 choices:
- Dinosaur footprints were found near the Grand Canyon.
- Fish were found living in the rivers of the Grand Canyon.
- Fossils of ocean animals were found at the Grand Canyon.
- Bones from desert animals were found at the Grand Canyon.

Could you tell me which one is correct?

Fossils of ocean animals were found at the Grand Canyon.