A scientist finds a fossil that she thinks might make a good index fossil.Which characteristic does this fossil most likely have?

A good index fossil comes from an organism that was widespread geographically but lived for a relatively short time. It should also be abundant, making it easier to find and recognize in rock layers. Being abundant nearby fits this characteristic; a narrow geographic range, as in choice D, makes a fossil less useful for correlating rocks across locations.

AI-written and checked against the verified answer.