What does an agonist do

A)  It extends the absolute refractory period of neural transmission. 
B)  It blocks the action of neurotransmitters. 
C)  It mimics the action of a neurotransmitter. 
D)  It prevents reuptake of neurotransmitters.

Agonist

A chemical or drug that binds to receptors in the brain and causes a reaction or response similar to a naturally occurring substance.

Absolute Refractory Period

a period immediately following the transmission of a nerve impulse when a neuron is not responsive to stimulation from another impulse.

Neurotransmitters

Chemical substances that transmit signals from one neuron to another across synapses.