Answer:
c. Glutamate
Step-by-step explanation:
Glutamate is commonly known as the most important excitatory neurotransmitter in the human body because of its significance in the proper function of our brains.
This neurotransmitter is responible for nerve signaling, that is, sending signals between neurons. Once glumatate is released into the synaptic cleft during long-term potentiation it plays a crucial role in learning and memory. Its role is to strengthen (or weaken) neuron signaling through time. This is important during synaptic plasticity as it significantly enhances learning.