Efferent nerve fibres are present in

a. somatic neural system
b. sympathetic neural system
c. para sympathetic neural system

Efferent nerve fibers are present in all three of the systems mentioned:

• Somatic Nervous System: Efferent nerve fibers in the somatic nervous system are responsible for carrying signals from the central nervous system (CNS) to skeletal muscles. These signals control voluntary muscle movements.
• Sympathetic Nervous System: Efferent nerve fibers in the sympathetic nervous system are part of the autonomic nervous system and are responsible for controlling involuntary functions, particularly the "fight or flight" response. They send signals to various organs and tissues to prepare the body for action in response to stress or danger.
• Parasympathetic Nervous System: Efferent nerve fibers in the parasympathetic nervous system, another division of the autonomic nervous system, are responsible for regulating various bodily functions during rest and recovery. They help promote relaxation and energy conservation.