Can you guys help me

Option C

Bones

Explanation:

Trace fossils (or ichnofossils) are geological records of biological activity. They are fossils, but not of the living things themselves.

Trace fossils may be impressions made on the substrate by an organism. Burrows, borings, footprints, bones, feeding marks, and root cavities are examples.

more words for this could be abiotic and biotic

abiotic: living organisms within an ecosystem

biotic: non-living organisms within an ecosystem

the wetland preservation movement began in the u.s. in earnest with the clean water act (cwa) of 1972. although not specifically written to protect wetlands, the cwa is comprised of a series of regulations designed to prevent pollutants from contaminating u.s. waters.