The answer is b are expensive
In a self-diagnosis situation, self-monitoring can help you determine any symptoms or behaviors, so you can pass them on to a doctor. Many have no real idea of what their behaviors or triggers are. Self-monitoring can help you gather that information first before meeting with a professional.
Answer: Motor neuron effector
If you accidentally touch hot surface, you automatically
pull your hand away from the object and this response is governed by a simple
combination of neurons called reflex arcs. The sensory neurons carriers the
impulse towards the central nervous system (CNS) then the interneuron carries
these impulses within the CNS, while the motor neuron carries impulse away from
CNS. Therefore, motor neuron is the last structure to respond to a reflex.