While Recording from a Neuron, Dr

While recording from a neuron, Dr. Chin noted that the neuron fired more rapidly as stimulus intensity was increased. But suddenly, the neuron would not fire any faster no matter how much the intensity was increased. What happened?

A) The neuron had failed to start reuptake.
B) Stimulus habituation.
C) The neuron was limited by the relative refractory period.
D) The neuron was limited by the absolute refractory period.
E) The synaptic vesicles began to use GABA.