Which statement explains why ammonites are a good example of an index fossil?(1 point)

Question

Responses

Ammonites existed for a relatively limited period of time.
Ammonites existed for a relatively limited period of time.

Ammonites existed only in the oceans.
Ammonites existed only in the oceans.

Ammonites existed long before the dinosaurs.
Ammonites existed long before the dinosaurs.

Ammonites existed in a small geographic area.

Answer 1

The correct statement that explains why ammonites are a good example of an index fossil is:

Ammonites existed for a relatively limited period of time.

Index fossils are used to identify and date the strata in which they are found, and the best index fossils are those that were widespread but existed for a relatively short geological time span. Ammonites fit this criterion well.