The largest number of neurons within the brain and spinal cord are responsible for the central nervous system's complex internal communications and intervene between inputs and outputs. these are the

Interneurons.

These interneurons transmit impulses to other neurons and thus form a part of the reflux arc.

step-by-step explanation:

we are given

we have to simplify it

firstly, we will factor it

now, we can cancel like terms

now, we can combine it

so, we get