7 special fossils that indicate to geologists the boundaries of geological tie. a index fossils b trace…

7 special fossils that indicate to geologists the boundaries of geological tie. a index fossils b trace fossils
Answer
Brief Explanations:
Index fossils are used by geologists to mark geological time - scale boundaries due to their short - lived and widespread nature. Trace fossils are signs of ancient organism activity and not used for time - scale boundaries in the same way.
Answer:
A. index fossils