which phrase describes organisms that formed index fossils?\nare extinct\nhad soft parts\nwere generally…
which phrase describes organisms that formed index fossils?\nare extinct\nhad soft parts\nwere generally large\nlived in a narrow geographic area
Answer
Answer:
A. are extinct
Brief Explanation:
Index fossils are from extinct organisms. They are used to date rock layers. Organisms with soft - parts don't fossilize well for index purposes. They aren't necessarily large and often had wide geographic distribution.