Which options are examples of trace fossils? 1. migration trails 2. animal burrows 3. skin of organism 4. preserved bones 5. footprints in mud

The correct answers are:

- migration trails;

- animals burrows;

- footprints in mud;

The trace fossils are special type of fossils that do not provide a direct evidence of the animals that lived in the past, but instead, they provide an indirect proof of it. That been said, the trace fossils contain traces from the lives of the animals, but not their physical structure.

A trace fossil can be anything from footprint in mud, animal burrows, a boring, tracks, even animal feces, and all of them give information about the lives of these animals, how they lived, where they migrated, what they ate etc.

a. i. only is correct.