Small bones and hair can be found in owl pellets, These things arent digestible thus leading to them being regurgitated whole.
The right option is; it interprets signals from the external environment
The peripheral nervous system (PNS) is made up of all parts of the nervous system, except the brain and spinal cord (parts of the central nervous system). The peripheral nervous system functions as a channel through which neural signals are transferred from and to the central nervous system. Two types of neurons (sensory and motor neurons) functions in the PNS. The motor neurons transfer neural signals from the central nervous system directly to various muscles, glands, and organs (effectors) throughout the body.
Oxygen , Carbon , hydrogen