Whether a Synapse Is Excitatory or Inhibitory Is Determined by the

Whether a synapse is excitatory or inhibitory is determined by the

A) number of action potentials arriving at the presynaptic axon terminal.
B) size of the calcium current flowing into the presynaptic axon terminal.
C) type of transmitter released by the presynaptic neuron and the receptor to which that transmitter binds on the postsynaptic neuron.
D) sensitivity of the postsynaptic membrane.