A Certain Neuron in a Mouse Brain Is Firing About

A certain neuron in a mouse brain is firing about 300 times per second, whereas almost all of its neighboring neurons are firing at much lower rates of only a few times per second. This implies that ...

A) this neuron expresses more depolarizing (Na⁺ and Ca²⁺) than hyperpolarizing (K⁺) channels compared to most of its neighbors.
B) the mouse is experiencing an epileptic seizure.
C) the refractory period of its voltage-gated Na⁺ channels is at least 300 ms.
D) it releases excitatory neurotransmitters at its axon terminals.
E) it is probably of a different type compared to most of its neighbors.