What is the theory of evolution by natural selection based upon? A. the fossil record only B. observations of living organisms only C. on both the fossil record and observations of living organisms D. on neither the fossil record nor observations of living organisms

Sariah enters a room with several chirping crickets in it. upon first entering the room, sariah can hear the chirping; however, as she begins to talk to her friends, she is no longer aware of the chirping even though it is still there. the fact that sariah no longer perceives the chirping sound demonstrates sensory