A bird watcher makes a sketch of the bird. A scientist discovers fossil remains of the bird. A researcher takes a photograph of the bird. A park ranger finds a suitable habitat for the bird.
I gave my students this multiple choice question: A species of bird has not been seen since the 1900s and is considered extinct. Which evidence would best disprove the claim that the bird is extinct?

Only one answer is correct among these 4 choices:
- A bird watcher makes a sketch of the bird.
- A scientist discovers fossil remains of the bird.
- A researcher takes a photograph of the bird.
- A park ranger finds a suitable habitat for the bird.

Could you tell me which one is correct?

A researcher takes a photograph of the bird.