Which Statement Characterizes the Relative Refractory Period

Multiple Choice

Which statement characterizes the relative refractory period?

A) The neuron cannot fire again because the potassium channels are unable to open.
B) The neuron cannot fire again because the sodium channels are unable to open.
C) The neuron can fire again but only to a stronger-than-threshold stimulus.
D) The neuron can fire again but only at a much slower rate.