Which of the following statements is false? (choose one)

a. voltage-gated sodium (na+) channels open in the dendrites and cell body during a local, graded potential.
b. during repolarization, potassium ions are leaving the cell (k+ is diffusing out of the cell), and the inside of the cell becomes more negative
c. if someone damaged an efferent motor neuron, they could feel pain, but not respond to move away from the pain
d. myelin serves as electrical insulation and increases the speed at which an action potential travels along the axon
e. movement of ions can be excitatory (if sodium ligand-gated channels bind the neurotransmitter), or inhibitory (if potassium ligand-gated channels bind the neurotransmitter)