Question

the image shows rock strata from three different regions on earth. identify all the layers that contain an index fossil.

Explanation:

Index fossils are fossils that are used to date the rock layers they are found in. They are widespread geographically and existed for a relatively short period of time. In the given image, the fossil labeled F4 appears in the same layer in all three regions. This indicates that it is likely an index fossil as it is widespread across different regions.

Answer:

The layer containing F4