Why is the speed of conduction through a reflex arc slower than the speed of conduction of an action potential along an axon?

    a.    There are greater amounts of myelin involved in the reflex arc.
    *b.    Transmission between neurons at synapses is slower than along axons.
    c.    Interneurons have thicker axons than other neurons.
    d.    The longer an axon, the slower its velocity.