The environment has changed. Animals need leafy trees. Rocks can destroy trees. Trees give off oxygen.
I gave my students this multiple choice question: The fossil record shows that trees have changed throughout the years. Which of the following conclusions would be best supported by the fossil record?

Only one answer is correct among these 4 choices:
- The environment has changed.
- Animals need leafy trees.
- Rocks can destroy trees.
- Trees give off oxygen.

Could you tell me which one is correct?

The environment has changed.