Answer:
B. Species C existed before species B.
Step-by-step explanation:
Sedimentary rocks are true "history books" containing fossils of the species that have lived. Each layer represents a specific time period where the deeper the layer, the older it is. Thus, as seen in the diagram, Species C is the oldest of them all. Thus it existed before species B and could not evolve from it, just as species B could not be a descendant of species A. It cannot be determined from the diagram if species A and B are genetically identical (most probably not as they are two different species) or which species was most abundant of them all.