Answer: biogeology
Step-by-step explanation:
Fossils are the remains of primitive dead organisms. These are found under the surface of earth crust. These are formed by the decomposition of the soft body parts of the living beings like tissues and organs by soil microbes but hard undegraded remains like bones, teeth, hard barks, and shells. These remain preserved under the heap of sediments. These sediments get compacted by heat and pressure inside the geosphere and these fossils get preserved in rocks.
On the basis of the above description, biogeology is the correct option. As fossil formation involves biological activity of decomposition by microbes and heat and pressure applied inside the geosphere. Hence, it is an example of biogeology.